Move reduced_ast.rs into multiple files
This commit is contained in:
Greg Shuflin
parent
0d488b250d
commit
2f669b77fd
@ -1,535 +0,0 @@
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//! # Reduced AST
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//! The reduced AST is a minimal AST designed to be built from the full AST after all possible
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//! static checks have been done. Consequently, the AST reduction phase does very little error
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//! checking itself - any errors should ideally be caught either by an earlier phase, or are
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//! runtime errors that the evaluator should handle. That said, becuase it does do table lookups
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//! that can in principle fail [especially at the moment with most static analysis not yet complete],
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//! there is an Expr variant `ReductionError` to handle these cases.
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//!
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//! A design decision to make - should the ReducedAST types contain all information about
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//! type/layout necessary for the evaluator to work? If so, then the evaluator should not
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//! have access to the symbol table at all and ReducedAST should carry that information. If not,
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//! then ReducedAST shouldn't be duplicating information that can be queried at runtime from the
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//! symbol table. But I think the former might make sense since ultimately the bytecode will be
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//! built from the ReducedAST.
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#![allow(clippy::enum_variant_names)]
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use std::rc::Rc;
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use std::str::FromStr;
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use std::convert::TryFrom;
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use crate::ast::*;
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use crate::symbol_table::{Symbol, SymbolSpec, SymbolTable};
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use crate::builtin::Builtin;
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use crate::util::deref_optional_box;
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#[derive(Debug)]
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pub struct ReducedAST(pub Vec<Stmt>);
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#[derive(Debug, Clone)]
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pub enum Stmt {
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PreBinding {
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name: Rc<String>,
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func: Func,
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},
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Binding {
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name: Rc<String>,
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constant: bool,
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expr: Expr,
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},
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Expr(Expr),
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Noop,
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}
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#[derive(Debug, Clone)]
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pub enum Expr {
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Unit,
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Lit(Lit),
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Sym(Rc<String>), //a Sym is anything that can be looked up by name at runtime - i.e. a function or variable address
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Tuple(Vec<Expr>),
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Func(Func),
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Constructor {
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type_name: Rc<String>,
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name: Rc<String>,
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tag: usize,
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arity: usize, // n.b. arity here is always the value from the symbol table - if it doesn't match what it's being called with, that's an eval error, eval will handle it
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},
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Call {
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f: Box<Expr>,
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args: Vec<Expr>,
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},
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Assign {
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val: Box<Expr>, //TODO this probably can't be a val
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expr: Box<Expr>,
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},
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Conditional {
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cond: Box<Expr>,
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then_clause: Vec<Stmt>,
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else_clause: Vec<Stmt>,
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},
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ConditionalTargetSigilValue,
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CaseMatch {
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cond: Box<Expr>,
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alternatives: Vec<Alternative>
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},
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UnimplementedSigilValue,
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ReductionError(String),
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}
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pub type BoundVars = Vec<Option<Rc<String>>>; //remember that order matters here
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#[derive(Debug, Clone)]
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pub struct Alternative {
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pub matchable: Subpattern,
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pub item: Vec<Stmt>,
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}
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#[derive(Debug, Clone)]
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pub struct Subpattern {
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pub tag: Option<usize>,
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pub subpatterns: Vec<Option<Subpattern>>,
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pub bound_vars: BoundVars,
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pub guard: Option<Expr>,
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}
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#[derive(Debug, Clone)]
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pub enum Lit {
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Nat(u64),
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Int(i64),
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Float(f64),
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Bool(bool),
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StringLit(Rc<String>),
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}
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#[derive(Debug, Clone)]
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pub enum Func {
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BuiltIn(Builtin),
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UserDefined {
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name: Option<Rc<String>>,
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params: Vec<Rc<String>>,
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body: Vec<Stmt>,
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}
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}
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pub fn reduce(ast: &AST, symbol_table: &SymbolTable) -> ReducedAST {
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let mut reducer = Reducer { symbol_table };
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reducer.ast(ast)
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}
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struct Reducer<'a> {
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symbol_table: &'a SymbolTable
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}
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impl<'a> Reducer<'a> {
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fn ast(&mut self, ast: &AST) -> ReducedAST {
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let mut output = vec![];
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for statement in ast.statements.iter() {
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output.push(self.statement(statement));
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}
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ReducedAST(output)
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}
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fn statement(&mut self, stmt: &Statement) -> Stmt {
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match &stmt.kind {
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StatementKind::Expression(expr) => Stmt::Expr(self.expression(expr)),
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StatementKind::Declaration(decl) => self.declaration(decl),
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StatementKind::Import(_) => Stmt::Noop,
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StatementKind::Module(modspec) => {
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for statement in modspec.contents.iter() {
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self.statement(statement);
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}
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Stmt::Noop
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}
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}
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}
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#[allow(clippy::ptr_arg)]
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fn block(&mut self, block: &Block) -> Vec<Stmt> {
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block.iter().map(|stmt| self.statement(stmt)).collect()
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}
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fn invocation_argument(&mut self, invoc: &InvocationArgument) -> Expr {
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use crate::ast::InvocationArgument::*;
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match invoc {
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Positional(ex) => self.expression(ex),
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Keyword { .. } => Expr::UnimplementedSigilValue,
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Ignored => Expr::UnimplementedSigilValue,
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}
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}
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fn expression(&mut self, expr: &Expression) -> Expr {
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use crate::ast::ExpressionKind::*;
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let input = &expr.kind;
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match input {
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NatLiteral(n) => Expr::Lit(Lit::Nat(*n)),
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FloatLiteral(f) => Expr::Lit(Lit::Float(*f)),
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StringLiteral(s) => Expr::Lit(Lit::StringLit(s.clone())),
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BoolLiteral(b) => Expr::Lit(Lit::Bool(*b)),
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BinExp(binop, lhs, rhs) => self.binop(binop, lhs, rhs),
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PrefixExp(op, arg) => self.prefix(op, arg),
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Value(qualified_name) => self.value(qualified_name),
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Call { f, arguments } => self.reduce_call_expression(f, arguments),
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TupleLiteral(exprs) => Expr::Tuple(exprs.iter().map(|e| self.expression(e)).collect()),
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IfExpression { discriminator, body } => self.reduce_if_expression(deref_optional_box(discriminator), body),
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Lambda { params, body, .. } => self.reduce_lambda(params, body),
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NamedStruct { name, fields } => self.reduce_named_struct(name, fields),
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Index { .. } => Expr::UnimplementedSigilValue,
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WhileExpression { .. } => Expr::UnimplementedSigilValue,
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ForExpression { .. } => Expr::UnimplementedSigilValue,
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ListLiteral { .. } => Expr::UnimplementedSigilValue,
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}
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}
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fn value(&mut self, qualified_name: &QualifiedName) -> Expr {
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let Symbol { local_name, spec, .. } = match self.symbol_table.lookup_symbol(&qualified_name.id) {
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Some(s) => s,
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//TODO this causes several evaluation tests to fail, figure out what's going on here
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//None => return Expr::ReductionError(format!("Symbol {:?} not found", sym_name)),
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None => {
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let name = qualified_name.components.last().unwrap().clone();
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return Expr::Sym(name)
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}
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};
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match spec {
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SymbolSpec::RecordConstructor { .. } => Expr::ReductionError("AST reducer doesn't expect a RecordConstructor here".to_string()),
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SymbolSpec::DataConstructor { index, arity, type_name } => Expr::Constructor {
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type_name: type_name.clone(),
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name: local_name.clone(),
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tag: *index,
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arity: *arity,
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},
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SymbolSpec::Func(_) => Expr::Sym(local_name.clone()),
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SymbolSpec::Binding => Expr::Sym(local_name.clone()), //TODO not sure if this is right, probably needs to eventually be fqsn
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}
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}
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#[allow(clippy::ptr_arg)]
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fn reduce_lambda(&mut self, params: &[FormalParam], body: &Block) -> Expr {
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Expr::Func(Func::UserDefined {
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name: None,
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params: params.iter().map(|param| param.name.clone()).collect(),
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body: self.block(body),
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})
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}
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fn reduce_named_struct(&mut self, name: &QualifiedName, fields: &[(Rc<String>, Expression)]) -> Expr {
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let symbol = match self.symbol_table.lookup_symbol(&name.id) {
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Some(fqsn) => fqsn,
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None => return Expr::ReductionError(format!("FQSN lookup for name {:?} failed", name)),
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};
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let (type_name, index, members_from_table) = match &symbol.spec {
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SymbolSpec::RecordConstructor { members, type_name, index } => (type_name.clone(), index, members),
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_ => return Expr::ReductionError("Not a record constructor".to_string()),
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};
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let arity = members_from_table.len();
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let mut args: Vec<(Rc<String>, Expr)> = fields.iter()
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.map(|(name, expr)| (name.clone(), self.expression(expr)))
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.collect();
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args.as_mut_slice()
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.sort_unstable_by(|(name1, _), (name2, _)| name1.cmp(name2)); //arbitrary - sorting by alphabetical order
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let args = args.into_iter().map(|(_, expr)| expr).collect();
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//TODO make sure this sorting actually works
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let f = box Expr::Constructor { type_name, name: symbol.local_name.clone(), tag: *index, arity, };
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Expr::Call { f, args }
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}
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fn reduce_call_expression(&mut self, func: &Expression, arguments: &[ InvocationArgument ]) -> Expr {
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Expr::Call {
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f: Box::new(self.expression(func)),
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args: arguments.iter().map(|arg| self.invocation_argument(arg)).collect(),
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}
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}
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fn reduce_if_expression(&mut self, discriminator: Option<&Expression>, body: &IfExpressionBody) -> Expr {
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let cond = Box::new(match discriminator {
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Some(expr) => self.expression(expr),
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None => return Expr::ReductionError("blank cond if-expr not supported".to_string()),
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});
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match body {
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IfExpressionBody::SimpleConditional { then_case, else_case } => {
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let then_clause = self.block(then_case);
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let else_clause = match else_case.as_ref() {
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None => vec![],
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Some(stmts) => self.block(stmts),
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};
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Expr::Conditional { cond, then_clause, else_clause }
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},
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IfExpressionBody::SimplePatternMatch { pattern, then_case, else_case } => {
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let then_clause = self.block(then_case);
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let else_clause = match else_case.as_ref() {
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None => vec![],
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Some(stmts) => self.block(stmts),
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};
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let alternatives = vec![
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pattern.to_alternative(then_clause, self.symbol_table),
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Alternative {
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matchable: Subpattern {
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tag: None,
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subpatterns: vec![],
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bound_vars: vec![],
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guard: None,
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},
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item: else_clause
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},
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];
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Expr::CaseMatch {
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cond,
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alternatives,
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}
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},
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IfExpressionBody::CondList(ref condition_arms) => {
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let mut alternatives = vec![];
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for arm in condition_arms {
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match arm.condition {
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Condition::Expression(ref _expr) => {
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return Expr::UnimplementedSigilValue
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},
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Condition::Pattern(ref p) => {
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let item = self.block(&arm.body);
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let alt = p.to_alternative(item, self.symbol_table);
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alternatives.push(alt);
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},
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Condition::TruncatedOp(_, _) => {
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return Expr::UnimplementedSigilValue
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},
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Condition::Else => {
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return Expr::UnimplementedSigilValue
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}
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}
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}
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Expr::CaseMatch { cond, alternatives }
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}
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}
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}
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fn binop(&mut self, binop: &BinOp, lhs: &Expression, rhs: &Expression) -> Expr {
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let operation = Builtin::from_str(binop.sigil()).ok();
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match operation {
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Some(Builtin::Assignment) => Expr::Assign {
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val: Box::new(self.expression(&*lhs)),
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expr: Box::new(self.expression(&*rhs)),
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},
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Some(op) => {
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let f = Box::new(Expr::Func(Func::BuiltIn(op)));
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Expr::Call { f, args: vec![self.expression(&*lhs), self.expression(&*rhs)] }
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},
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None => {
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//TODO handle a user-defined operation
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Expr::UnimplementedSigilValue
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}
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}
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}
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fn prefix(&mut self, prefix: &PrefixOp, arg: &Expression) -> Expr {
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let builtin: Option<Builtin> = TryFrom::try_from(prefix).ok();
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match builtin {
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Some(op) => {
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let f = Box::new(Expr::Func(Func::BuiltIn(op)));
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Expr::Call { f, args: vec![self.expression(arg)] }
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},
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None => { //TODO need this for custom prefix ops
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Expr::UnimplementedSigilValue
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}
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}
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}
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fn declaration(&mut self, declaration: &Declaration) -> Stmt {
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use self::Declaration::*;
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match declaration {
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Binding {name, constant, expr, .. } => Stmt::Binding { name: name.clone(), constant: *constant, expr: self.expression(expr) },
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FuncDecl(Signature { name, params, .. }, statements) => Stmt::PreBinding {
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name: name.clone(),
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func: Func::UserDefined {
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name: Some(name.clone()),
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params: params.iter().map(|param| param.name.clone()).collect(),
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body: self.block(statements),
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}
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},
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TypeDecl { .. } => Stmt::Noop,
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TypeAlias{ .. } => Stmt::Noop,
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Interface { .. } => Stmt::Noop,
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Impl { .. } => Stmt::Expr(Expr::UnimplementedSigilValue),
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_ => Stmt::Expr(Expr::UnimplementedSigilValue)
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}
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}
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}
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/* ig var pat
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* x is SomeBigOldEnum(_, x, Some(t))
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*/
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fn handle_symbol(symbol: Option<&Symbol>, inner_patterns: &[Pattern], symbol_table: &SymbolTable) -> Subpattern {
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use self::Pattern::*;
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let tag = symbol.map(|symbol| match symbol.spec {
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||||||
SymbolSpec::DataConstructor { index, .. } => index,
|
|
||||||
_ => panic!("Symbol is not a data constructor - this should've been caught in type-checking"),
|
|
||||||
});
|
|
||||||
let bound_vars = inner_patterns.iter().map(|p| match p {
|
|
||||||
VarOrName(qualified_name) => {
|
|
||||||
let symbol_exists = symbol_table.lookup_symbol(&qualified_name.id).is_some();
|
|
||||||
if symbol_exists {
|
|
||||||
None
|
|
||||||
} else {
|
|
||||||
let QualifiedName { components, .. } = qualified_name;
|
|
||||||
if components.len() == 1 {
|
|
||||||
Some(components[0].clone())
|
|
||||||
} else {
|
|
||||||
panic!("Bad variable name in pattern");
|
|
||||||
}
|
|
||||||
}
|
|
||||||
},
|
|
||||||
_ => None,
|
|
||||||
}).collect();
|
|
||||||
|
|
||||||
let subpatterns = inner_patterns.iter().map(|p| match p {
|
|
||||||
Ignored => None,
|
|
||||||
VarOrName(_) => None,
|
|
||||||
Literal(other) => Some(other.to_subpattern(symbol_table)),
|
|
||||||
tp @ TuplePattern(_) => Some(tp.to_subpattern(symbol_table)),
|
|
||||||
ts @ TupleStruct(_, _) => Some(ts.to_subpattern(symbol_table)),
|
|
||||||
Record(..) => unimplemented!(),
|
|
||||||
}).collect();
|
|
||||||
|
|
||||||
let guard = None;
|
|
||||||
/*
|
|
||||||
let guard_equality_exprs: Vec<Expr> = subpatterns.iter().map(|p| match p {
|
|
||||||
Literal(lit) => match lit {
|
|
||||||
_ => unimplemented!()
|
|
||||||
},
|
|
||||||
_ => unimplemented!()
|
|
||||||
}).collect();
|
|
||||||
*/
|
|
||||||
|
|
||||||
Subpattern {
|
|
||||||
tag,
|
|
||||||
subpatterns,
|
|
||||||
guard,
|
|
||||||
bound_vars,
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
impl Pattern {
|
|
||||||
fn to_alternative(&self, item: Vec<Stmt>, symbol_table: &SymbolTable) -> Alternative {
|
|
||||||
let s = self.to_subpattern(symbol_table);
|
|
||||||
Alternative {
|
|
||||||
matchable: Subpattern {
|
|
||||||
tag: s.tag,
|
|
||||||
subpatterns: s.subpatterns,
|
|
||||||
bound_vars: s.bound_vars,
|
|
||||||
guard: s.guard,
|
|
||||||
},
|
|
||||||
item
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
fn to_subpattern(&self, symbol_table: &SymbolTable) -> Subpattern {
|
|
||||||
use self::Pattern::*;
|
|
||||||
match self {
|
|
||||||
TupleStruct(QualifiedName{ components, id }, inner_patterns) => {
|
|
||||||
match symbol_table.lookup_symbol(id) {
|
|
||||||
Some(symbol) => handle_symbol(Some(symbol), inner_patterns, symbol_table),
|
|
||||||
None => panic!("Symbol {:?} not found", components)
|
|
||||||
}
|
|
||||||
},
|
|
||||||
TuplePattern(inner_patterns) => handle_symbol(None, inner_patterns, symbol_table),
|
|
||||||
Record(_name, _pairs) => {
|
|
||||||
unimplemented!()
|
|
||||||
},
|
|
||||||
Ignored => Subpattern { tag: None, subpatterns: vec![], guard: None, bound_vars: vec![] },
|
|
||||||
Literal(lit) => lit.to_subpattern(symbol_table),
|
|
||||||
VarOrName(QualifiedName { components, id }) => {
|
|
||||||
// if symbol is Some, treat this as a symbol pattern. If it's None, treat it
|
|
||||||
// as a variable.
|
|
||||||
match symbol_table.lookup_symbol(id) {
|
|
||||||
Some(symbol) => handle_symbol(Some(symbol), &[], symbol_table),
|
|
||||||
None => {
|
|
||||||
println!("Components: {:?}", components);
|
|
||||||
let name = if components.len() == 1 {
|
|
||||||
components[0].clone()
|
|
||||||
} else {
|
|
||||||
panic!("check this line of code yo");
|
|
||||||
};
|
|
||||||
Subpattern {
|
|
||||||
tag: None,
|
|
||||||
subpatterns: vec![],
|
|
||||||
guard: None,
|
|
||||||
bound_vars: vec![Some(name)],
|
|
||||||
}
|
|
||||||
}
|
|
||||||
}
|
|
||||||
},
|
|
||||||
}
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
impl PatternLiteral {
|
|
||||||
fn to_subpattern(&self, _symbol_table: &SymbolTable) -> Subpattern {
|
|
||||||
use self::PatternLiteral::*;
|
|
||||||
match self {
|
|
||||||
NumPattern { neg, num } => {
|
|
||||||
let comparison = Expr::Lit(match (neg, num) {
|
|
||||||
(false, ExpressionKind::NatLiteral(n)) => Lit::Nat(*n),
|
|
||||||
(false, ExpressionKind::FloatLiteral(f)) => Lit::Float(*f),
|
|
||||||
(true, ExpressionKind::NatLiteral(n)) => Lit::Int(-(*n as i64)),
|
|
||||||
(true, ExpressionKind::FloatLiteral(f)) => Lit::Float(-f),
|
|
||||||
_ => panic!("This should never happen")
|
|
||||||
});
|
|
||||||
let guard = Some(Expr::Call {
|
|
||||||
f: Box::new(Expr::Func(Func::BuiltIn(Builtin::Equality))),
|
|
||||||
args: vec![comparison, Expr::ConditionalTargetSigilValue],
|
|
||||||
});
|
|
||||||
Subpattern {
|
|
||||||
tag: None,
|
|
||||||
subpatterns: vec![],
|
|
||||||
guard,
|
|
||||||
bound_vars: vec![],
|
|
||||||
}
|
|
||||||
},
|
|
||||||
StringPattern(s) => {
|
|
||||||
let guard = Some(Expr::Call {
|
|
||||||
f: Box::new(Expr::Func(Func::BuiltIn(Builtin::Equality))),
|
|
||||||
args: vec![Expr::Lit(Lit::StringLit(s.clone())), Expr::ConditionalTargetSigilValue]
|
|
||||||
});
|
|
||||||
|
|
||||||
Subpattern {
|
|
||||||
tag: None,
|
|
||||||
subpatterns: vec![],
|
|
||||||
guard,
|
|
||||||
bound_vars: vec![],
|
|
||||||
}
|
|
||||||
},
|
|
||||||
BoolPattern(b) => {
|
|
||||||
let guard = Some(if *b {
|
|
||||||
Expr::ConditionalTargetSigilValue
|
|
||||||
} else {
|
|
||||||
Expr::Call {
|
|
||||||
f: Box::new(Expr::Func(Func::BuiltIn(Builtin::BooleanNot))),
|
|
||||||
args: vec![Expr::ConditionalTargetSigilValue]
|
|
||||||
}
|
|
||||||
});
|
|
||||||
Subpattern {
|
|
||||||
tag: None,
|
|
||||||
subpatterns: vec![],
|
|
||||||
guard,
|
|
||||||
bound_vars: vec![],
|
|
||||||
}
|
|
||||||
},
|
|
||||||
}
|
|
||||||
}
|
|
||||||
|
|
||||||
}
|
|
||||||
513
schala-lang/language/src/reduced_ast/mod.rs
Normal file
513
schala-lang/language/src/reduced_ast/mod.rs
Normal file
@ -0,0 +1,513 @@
|
|||||||
|
//! # Reduced AST
|
||||||
|
//! The reduced AST is a minimal AST designed to be built from the full AST after all possible
|
||||||
|
//! static checks have been done. Consequently, the AST reduction phase does very little error
|
||||||
|
//! checking itself - any errors should ideally be caught either by an earlier phase, or are
|
||||||
|
//! runtime errors that the evaluator should handle. That said, becuase it does do table lookups
|
||||||
|
//! that can in principle fail [especially at the moment with most static analysis not yet complete],
|
||||||
|
//! there is an Expr variant `ReductionError` to handle these cases.
|
||||||
|
//!
|
||||||
|
//! A design decision to make - should the ReducedAST types contain all information about
|
||||||
|
//! type/layout necessary for the evaluator to work? If so, then the evaluator should not
|
||||||
|
//! have access to the symbol table at all and ReducedAST should carry that information. If not,
|
||||||
|
//! then ReducedAST shouldn't be duplicating information that can be queried at runtime from the
|
||||||
|
//! symbol table. But I think the former might make sense since ultimately the bytecode will be
|
||||||
|
//! built from the ReducedAST.
|
||||||
|
|
||||||
|
use std::convert::TryFrom;
|
||||||
|
use std::rc::Rc;
|
||||||
|
use std::str::FromStr;
|
||||||
|
|
||||||
|
use crate::ast::*;
|
||||||
|
use crate::builtin::Builtin;
|
||||||
|
use crate::symbol_table::{Symbol, SymbolSpec, SymbolTable};
|
||||||
|
use crate::util::deref_optional_box;
|
||||||
|
|
||||||
|
mod types;
|
||||||
|
pub use types::*;
|
||||||
|
|
||||||
|
pub fn reduce(ast: &AST, symbol_table: &SymbolTable) -> ReducedAST {
|
||||||
|
let mut reducer = Reducer { symbol_table };
|
||||||
|
reducer.ast(ast)
|
||||||
|
}
|
||||||
|
|
||||||
|
struct Reducer<'a> {
|
||||||
|
symbol_table: &'a SymbolTable,
|
||||||
|
}
|
||||||
|
|
||||||
|
impl<'a> Reducer<'a> {
|
||||||
|
fn ast(&mut self, ast: &AST) -> ReducedAST {
|
||||||
|
let mut output = vec![];
|
||||||
|
for statement in ast.statements.iter() {
|
||||||
|
output.push(self.statement(statement));
|
||||||
|
}
|
||||||
|
ReducedAST(output)
|
||||||
|
}
|
||||||
|
|
||||||
|
fn statement(&mut self, stmt: &Statement) -> Stmt {
|
||||||
|
match &stmt.kind {
|
||||||
|
StatementKind::Expression(expr) => Stmt::Expr(self.expression(expr)),
|
||||||
|
StatementKind::Declaration(decl) => self.declaration(decl),
|
||||||
|
StatementKind::Import(_) => Stmt::Noop,
|
||||||
|
StatementKind::Module(modspec) => {
|
||||||
|
for statement in modspec.contents.iter() {
|
||||||
|
self.statement(statement);
|
||||||
|
}
|
||||||
|
Stmt::Noop
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
#[allow(clippy::ptr_arg)]
|
||||||
|
fn block(&mut self, block: &Block) -> Vec<Stmt> {
|
||||||
|
block.iter().map(|stmt| self.statement(stmt)).collect()
|
||||||
|
}
|
||||||
|
|
||||||
|
fn invocation_argument(&mut self, invoc: &InvocationArgument) -> Expr {
|
||||||
|
use crate::ast::InvocationArgument::*;
|
||||||
|
match invoc {
|
||||||
|
Positional(ex) => self.expression(ex),
|
||||||
|
Keyword { .. } => Expr::UnimplementedSigilValue,
|
||||||
|
Ignored => Expr::UnimplementedSigilValue,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
fn expression(&mut self, expr: &Expression) -> Expr {
|
||||||
|
use crate::ast::ExpressionKind::*;
|
||||||
|
let input = &expr.kind;
|
||||||
|
match input {
|
||||||
|
NatLiteral(n) => Expr::Lit(Lit::Nat(*n)),
|
||||||
|
FloatLiteral(f) => Expr::Lit(Lit::Float(*f)),
|
||||||
|
StringLiteral(s) => Expr::Lit(Lit::StringLit(s.clone())),
|
||||||
|
BoolLiteral(b) => Expr::Lit(Lit::Bool(*b)),
|
||||||
|
BinExp(binop, lhs, rhs) => self.binop(binop, lhs, rhs),
|
||||||
|
PrefixExp(op, arg) => self.prefix(op, arg),
|
||||||
|
Value(qualified_name) => self.value(qualified_name),
|
||||||
|
Call { f, arguments } => self.reduce_call_expression(f, arguments),
|
||||||
|
TupleLiteral(exprs) => Expr::Tuple(exprs.iter().map(|e| self.expression(e)).collect()),
|
||||||
|
IfExpression {
|
||||||
|
discriminator,
|
||||||
|
body,
|
||||||
|
} => self.reduce_if_expression(deref_optional_box(discriminator), body),
|
||||||
|
Lambda { params, body, .. } => self.reduce_lambda(params, body),
|
||||||
|
NamedStruct { name, fields } => self.reduce_named_struct(name, fields),
|
||||||
|
Index { .. } => Expr::UnimplementedSigilValue,
|
||||||
|
WhileExpression { .. } => Expr::UnimplementedSigilValue,
|
||||||
|
ForExpression { .. } => Expr::UnimplementedSigilValue,
|
||||||
|
ListLiteral { .. } => Expr::UnimplementedSigilValue,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
fn value(&mut self, qualified_name: &QualifiedName) -> Expr {
|
||||||
|
let Symbol {
|
||||||
|
local_name, spec, ..
|
||||||
|
} = match self.symbol_table.lookup_symbol(&qualified_name.id) {
|
||||||
|
Some(s) => s,
|
||||||
|
//TODO this causes several evaluation tests to fail, figure out what's going on here
|
||||||
|
//None => return Expr::ReductionError(format!("Symbol {:?} not found", sym_name)),
|
||||||
|
None => {
|
||||||
|
let name = qualified_name.components.last().unwrap().clone();
|
||||||
|
return Expr::Sym(name);
|
||||||
|
}
|
||||||
|
};
|
||||||
|
|
||||||
|
match spec {
|
||||||
|
SymbolSpec::RecordConstructor { .. } => Expr::ReductionError(
|
||||||
|
"AST reducer doesn't expect a RecordConstructor here".to_string(),
|
||||||
|
),
|
||||||
|
SymbolSpec::DataConstructor {
|
||||||
|
index,
|
||||||
|
arity,
|
||||||
|
type_name,
|
||||||
|
} => Expr::Constructor {
|
||||||
|
type_name: type_name.clone(),
|
||||||
|
name: local_name.clone(),
|
||||||
|
tag: *index,
|
||||||
|
arity: *arity,
|
||||||
|
},
|
||||||
|
SymbolSpec::Func(_) => Expr::Sym(local_name.clone()),
|
||||||
|
SymbolSpec::Binding => Expr::Sym(local_name.clone()), //TODO not sure if this is right, probably needs to eventually be fqsn
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
#[allow(clippy::ptr_arg)]
|
||||||
|
fn reduce_lambda(&mut self, params: &[FormalParam], body: &Block) -> Expr {
|
||||||
|
Expr::Func(Func::UserDefined {
|
||||||
|
name: None,
|
||||||
|
params: params.iter().map(|param| param.name.clone()).collect(),
|
||||||
|
body: self.block(body),
|
||||||
|
})
|
||||||
|
}
|
||||||
|
|
||||||
|
fn reduce_named_struct(
|
||||||
|
&mut self,
|
||||||
|
name: &QualifiedName,
|
||||||
|
fields: &[(Rc<String>, Expression)],
|
||||||
|
) -> Expr {
|
||||||
|
let symbol = match self.symbol_table.lookup_symbol(&name.id) {
|
||||||
|
Some(fqsn) => fqsn,
|
||||||
|
None => return Expr::ReductionError(format!("FQSN lookup for name {:?} failed", name)),
|
||||||
|
};
|
||||||
|
|
||||||
|
let (type_name, index, members_from_table) = match &symbol.spec {
|
||||||
|
SymbolSpec::RecordConstructor {
|
||||||
|
members,
|
||||||
|
type_name,
|
||||||
|
index,
|
||||||
|
} => (type_name.clone(), index, members),
|
||||||
|
_ => return Expr::ReductionError("Not a record constructor".to_string()),
|
||||||
|
};
|
||||||
|
|
||||||
|
let arity = members_from_table.len();
|
||||||
|
|
||||||
|
let mut args: Vec<(Rc<String>, Expr)> = fields
|
||||||
|
.iter()
|
||||||
|
.map(|(name, expr)| (name.clone(), self.expression(expr)))
|
||||||
|
.collect();
|
||||||
|
|
||||||
|
args.as_mut_slice()
|
||||||
|
.sort_unstable_by(|(name1, _), (name2, _)| name1.cmp(name2)); //arbitrary - sorting by alphabetical order
|
||||||
|
|
||||||
|
let args = args.into_iter().map(|(_, expr)| expr).collect();
|
||||||
|
|
||||||
|
//TODO make sure this sorting actually works
|
||||||
|
let f = box Expr::Constructor {
|
||||||
|
type_name,
|
||||||
|
name: symbol.local_name.clone(),
|
||||||
|
tag: *index,
|
||||||
|
arity,
|
||||||
|
};
|
||||||
|
Expr::Call { f, args }
|
||||||
|
}
|
||||||
|
|
||||||
|
fn reduce_call_expression(
|
||||||
|
&mut self,
|
||||||
|
func: &Expression,
|
||||||
|
arguments: &[InvocationArgument],
|
||||||
|
) -> Expr {
|
||||||
|
Expr::Call {
|
||||||
|
f: Box::new(self.expression(func)),
|
||||||
|
args: arguments
|
||||||
|
.iter()
|
||||||
|
.map(|arg| self.invocation_argument(arg))
|
||||||
|
.collect(),
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
fn reduce_if_expression(
|
||||||
|
&mut self,
|
||||||
|
discriminator: Option<&Expression>,
|
||||||
|
body: &IfExpressionBody,
|
||||||
|
) -> Expr {
|
||||||
|
let cond = Box::new(match discriminator {
|
||||||
|
Some(expr) => self.expression(expr),
|
||||||
|
None => return Expr::ReductionError("blank cond if-expr not supported".to_string()),
|
||||||
|
});
|
||||||
|
|
||||||
|
match body {
|
||||||
|
IfExpressionBody::SimpleConditional {
|
||||||
|
then_case,
|
||||||
|
else_case,
|
||||||
|
} => {
|
||||||
|
let then_clause = self.block(then_case);
|
||||||
|
let else_clause = match else_case.as_ref() {
|
||||||
|
None => vec![],
|
||||||
|
Some(stmts) => self.block(stmts),
|
||||||
|
};
|
||||||
|
Expr::Conditional {
|
||||||
|
cond,
|
||||||
|
then_clause,
|
||||||
|
else_clause,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
IfExpressionBody::SimplePatternMatch {
|
||||||
|
pattern,
|
||||||
|
then_case,
|
||||||
|
else_case,
|
||||||
|
} => {
|
||||||
|
let then_clause = self.block(then_case);
|
||||||
|
let else_clause = match else_case.as_ref() {
|
||||||
|
None => vec![],
|
||||||
|
Some(stmts) => self.block(stmts),
|
||||||
|
};
|
||||||
|
|
||||||
|
let alternatives = vec![
|
||||||
|
pattern.to_alternative(then_clause, self.symbol_table),
|
||||||
|
Alternative {
|
||||||
|
matchable: Subpattern {
|
||||||
|
tag: None,
|
||||||
|
subpatterns: vec![],
|
||||||
|
bound_vars: vec![],
|
||||||
|
guard: None,
|
||||||
|
},
|
||||||
|
item: else_clause,
|
||||||
|
},
|
||||||
|
];
|
||||||
|
|
||||||
|
Expr::CaseMatch { cond, alternatives }
|
||||||
|
}
|
||||||
|
IfExpressionBody::CondList(ref condition_arms) => {
|
||||||
|
let mut alternatives = vec![];
|
||||||
|
for arm in condition_arms {
|
||||||
|
match arm.condition {
|
||||||
|
Condition::Expression(ref _expr) => return Expr::UnimplementedSigilValue,
|
||||||
|
Condition::Pattern(ref p) => {
|
||||||
|
let item = self.block(&arm.body);
|
||||||
|
let alt = p.to_alternative(item, self.symbol_table);
|
||||||
|
alternatives.push(alt);
|
||||||
|
}
|
||||||
|
Condition::TruncatedOp(_, _) => return Expr::UnimplementedSigilValue,
|
||||||
|
Condition::Else => return Expr::UnimplementedSigilValue,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
Expr::CaseMatch { cond, alternatives }
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
fn binop(&mut self, binop: &BinOp, lhs: &Expression, rhs: &Expression) -> Expr {
|
||||||
|
let operation = Builtin::from_str(binop.sigil()).ok();
|
||||||
|
match operation {
|
||||||
|
Some(Builtin::Assignment) => Expr::Assign {
|
||||||
|
val: Box::new(self.expression(&*lhs)),
|
||||||
|
expr: Box::new(self.expression(&*rhs)),
|
||||||
|
},
|
||||||
|
Some(op) => {
|
||||||
|
let f = Box::new(Expr::Func(Func::BuiltIn(op)));
|
||||||
|
Expr::Call {
|
||||||
|
f,
|
||||||
|
args: vec![self.expression(&*lhs), self.expression(&*rhs)],
|
||||||
|
}
|
||||||
|
}
|
||||||
|
None => {
|
||||||
|
//TODO handle a user-defined operation
|
||||||
|
Expr::UnimplementedSigilValue
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
fn prefix(&mut self, prefix: &PrefixOp, arg: &Expression) -> Expr {
|
||||||
|
let builtin: Option<Builtin> = TryFrom::try_from(prefix).ok();
|
||||||
|
match builtin {
|
||||||
|
Some(op) => {
|
||||||
|
let f = Box::new(Expr::Func(Func::BuiltIn(op)));
|
||||||
|
Expr::Call {
|
||||||
|
f,
|
||||||
|
args: vec![self.expression(arg)],
|
||||||
|
}
|
||||||
|
}
|
||||||
|
None => {
|
||||||
|
//TODO need this for custom prefix ops
|
||||||
|
Expr::UnimplementedSigilValue
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
fn declaration(&mut self, declaration: &Declaration) -> Stmt {
|
||||||
|
use self::Declaration::*;
|
||||||
|
match declaration {
|
||||||
|
Binding {
|
||||||
|
name,
|
||||||
|
constant,
|
||||||
|
expr,
|
||||||
|
..
|
||||||
|
} => Stmt::Binding {
|
||||||
|
name: name.clone(),
|
||||||
|
constant: *constant,
|
||||||
|
expr: self.expression(expr),
|
||||||
|
},
|
||||||
|
FuncDecl(Signature { name, params, .. }, statements) => Stmt::PreBinding {
|
||||||
|
name: name.clone(),
|
||||||
|
func: Func::UserDefined {
|
||||||
|
name: Some(name.clone()),
|
||||||
|
params: params.iter().map(|param| param.name.clone()).collect(),
|
||||||
|
body: self.block(statements),
|
||||||
|
},
|
||||||
|
},
|
||||||
|
TypeDecl { .. } => Stmt::Noop,
|
||||||
|
TypeAlias { .. } => Stmt::Noop,
|
||||||
|
Interface { .. } => Stmt::Noop,
|
||||||
|
Impl { .. } => Stmt::Expr(Expr::UnimplementedSigilValue),
|
||||||
|
_ => Stmt::Expr(Expr::UnimplementedSigilValue),
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
fn handle_symbol(
|
||||||
|
symbol: Option<&Symbol>,
|
||||||
|
inner_patterns: &[Pattern],
|
||||||
|
symbol_table: &SymbolTable,
|
||||||
|
) -> Subpattern {
|
||||||
|
use self::Pattern::*;
|
||||||
|
let tag = symbol.map(|symbol| match symbol.spec {
|
||||||
|
SymbolSpec::DataConstructor { index, .. } => index,
|
||||||
|
_ => {
|
||||||
|
panic!("Symbol is not a data constructor - this should've been caught in type-checking")
|
||||||
|
}
|
||||||
|
});
|
||||||
|
let bound_vars = inner_patterns
|
||||||
|
.iter()
|
||||||
|
.map(|p| match p {
|
||||||
|
VarOrName(qualified_name) => {
|
||||||
|
let symbol_exists = symbol_table.lookup_symbol(&qualified_name.id).is_some();
|
||||||
|
if symbol_exists {
|
||||||
|
None
|
||||||
|
} else {
|
||||||
|
let QualifiedName { components, .. } = qualified_name;
|
||||||
|
if components.len() == 1 {
|
||||||
|
Some(components[0].clone())
|
||||||
|
} else {
|
||||||
|
panic!("Bad variable name in pattern");
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
_ => None,
|
||||||
|
})
|
||||||
|
.collect();
|
||||||
|
|
||||||
|
let subpatterns = inner_patterns
|
||||||
|
.iter()
|
||||||
|
.map(|p| match p {
|
||||||
|
Ignored => None,
|
||||||
|
VarOrName(_) => None,
|
||||||
|
Literal(other) => Some(other.to_subpattern(symbol_table)),
|
||||||
|
tp @ TuplePattern(_) => Some(tp.to_subpattern(symbol_table)),
|
||||||
|
ts @ TupleStruct(_, _) => Some(ts.to_subpattern(symbol_table)),
|
||||||
|
Record(..) => unimplemented!(),
|
||||||
|
})
|
||||||
|
.collect();
|
||||||
|
|
||||||
|
let guard = None;
|
||||||
|
/*
|
||||||
|
let guard_equality_exprs: Vec<Expr> = subpatterns.iter().map(|p| match p {
|
||||||
|
Literal(lit) => match lit {
|
||||||
|
_ => unimplemented!()
|
||||||
|
},
|
||||||
|
_ => unimplemented!()
|
||||||
|
}).collect();
|
||||||
|
*/
|
||||||
|
|
||||||
|
Subpattern {
|
||||||
|
tag,
|
||||||
|
subpatterns,
|
||||||
|
guard,
|
||||||
|
bound_vars,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
impl Pattern {
|
||||||
|
fn to_alternative(&self, item: Vec<Stmt>, symbol_table: &SymbolTable) -> Alternative {
|
||||||
|
let s = self.to_subpattern(symbol_table);
|
||||||
|
Alternative {
|
||||||
|
matchable: Subpattern {
|
||||||
|
tag: s.tag,
|
||||||
|
subpatterns: s.subpatterns,
|
||||||
|
bound_vars: s.bound_vars,
|
||||||
|
guard: s.guard,
|
||||||
|
},
|
||||||
|
item,
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
fn to_subpattern(&self, symbol_table: &SymbolTable) -> Subpattern {
|
||||||
|
use self::Pattern::*;
|
||||||
|
match self {
|
||||||
|
TupleStruct(QualifiedName { components, id }, inner_patterns) => {
|
||||||
|
match symbol_table.lookup_symbol(id) {
|
||||||
|
Some(symbol) => handle_symbol(Some(symbol), inner_patterns, symbol_table),
|
||||||
|
None => panic!("Symbol {:?} not found", components),
|
||||||
|
}
|
||||||
|
}
|
||||||
|
TuplePattern(inner_patterns) => handle_symbol(None, inner_patterns, symbol_table),
|
||||||
|
Record(_name, _pairs) => {
|
||||||
|
unimplemented!()
|
||||||
|
}
|
||||||
|
Ignored => Subpattern {
|
||||||
|
tag: None,
|
||||||
|
subpatterns: vec![],
|
||||||
|
guard: None,
|
||||||
|
bound_vars: vec![],
|
||||||
|
},
|
||||||
|
Literal(lit) => lit.to_subpattern(symbol_table),
|
||||||
|
VarOrName(QualifiedName { components, id }) => {
|
||||||
|
// if symbol is Some, treat this as a symbol pattern. If it's None, treat it
|
||||||
|
// as a variable.
|
||||||
|
match symbol_table.lookup_symbol(id) {
|
||||||
|
Some(symbol) => handle_symbol(Some(symbol), &[], symbol_table),
|
||||||
|
None => {
|
||||||
|
println!("Components: {:?}", components);
|
||||||
|
let name = if components.len() == 1 {
|
||||||
|
components[0].clone()
|
||||||
|
} else {
|
||||||
|
panic!("check this line of code yo");
|
||||||
|
};
|
||||||
|
Subpattern {
|
||||||
|
tag: None,
|
||||||
|
subpatterns: vec![],
|
||||||
|
guard: None,
|
||||||
|
bound_vars: vec![Some(name)],
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
impl PatternLiteral {
|
||||||
|
fn to_subpattern(&self, _symbol_table: &SymbolTable) -> Subpattern {
|
||||||
|
use self::PatternLiteral::*;
|
||||||
|
match self {
|
||||||
|
NumPattern { neg, num } => {
|
||||||
|
let comparison = Expr::Lit(match (neg, num) {
|
||||||
|
(false, ExpressionKind::NatLiteral(n)) => Lit::Nat(*n),
|
||||||
|
(false, ExpressionKind::FloatLiteral(f)) => Lit::Float(*f),
|
||||||
|
(true, ExpressionKind::NatLiteral(n)) => Lit::Int(-(*n as i64)),
|
||||||
|
(true, ExpressionKind::FloatLiteral(f)) => Lit::Float(-f),
|
||||||
|
_ => panic!("This should never happen"),
|
||||||
|
});
|
||||||
|
let guard = Some(Expr::Call {
|
||||||
|
f: Box::new(Expr::Func(Func::BuiltIn(Builtin::Equality))),
|
||||||
|
args: vec![comparison, Expr::ConditionalTargetSigilValue],
|
||||||
|
});
|
||||||
|
Subpattern {
|
||||||
|
tag: None,
|
||||||
|
subpatterns: vec![],
|
||||||
|
guard,
|
||||||
|
bound_vars: vec![],
|
||||||
|
}
|
||||||
|
}
|
||||||
|
StringPattern(s) => {
|
||||||
|
let guard = Some(Expr::Call {
|
||||||
|
f: Box::new(Expr::Func(Func::BuiltIn(Builtin::Equality))),
|
||||||
|
args: vec![
|
||||||
|
Expr::Lit(Lit::StringLit(s.clone())),
|
||||||
|
Expr::ConditionalTargetSigilValue,
|
||||||
|
],
|
||||||
|
});
|
||||||
|
|
||||||
|
Subpattern {
|
||||||
|
tag: None,
|
||||||
|
subpatterns: vec![],
|
||||||
|
guard,
|
||||||
|
bound_vars: vec![],
|
||||||
|
}
|
||||||
|
}
|
||||||
|
BoolPattern(b) => {
|
||||||
|
let guard = Some(if *b {
|
||||||
|
Expr::ConditionalTargetSigilValue
|
||||||
|
} else {
|
||||||
|
Expr::Call {
|
||||||
|
f: Box::new(Expr::Func(Func::BuiltIn(Builtin::BooleanNot))),
|
||||||
|
args: vec![Expr::ConditionalTargetSigilValue],
|
||||||
|
}
|
||||||
|
});
|
||||||
|
Subpattern {
|
||||||
|
tag: None,
|
||||||
|
subpatterns: vec![],
|
||||||
|
guard,
|
||||||
|
bound_vars: vec![],
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
92
schala-lang/language/src/reduced_ast/types.rs
Normal file
92
schala-lang/language/src/reduced_ast/types.rs
Normal file
@ -0,0 +1,92 @@
|
|||||||
|
#![allow(clippy::enum_variant_names)]
|
||||||
|
|
||||||
|
use crate::builtin::Builtin;
|
||||||
|
use std::rc::Rc;
|
||||||
|
|
||||||
|
#[derive(Debug)]
|
||||||
|
pub struct ReducedAST(pub Vec<Stmt>);
|
||||||
|
|
||||||
|
#[derive(Debug, Clone)]
|
||||||
|
pub enum Stmt {
|
||||||
|
PreBinding {
|
||||||
|
name: Rc<String>,
|
||||||
|
func: Func,
|
||||||
|
},
|
||||||
|
Binding {
|
||||||
|
name: Rc<String>,
|
||||||
|
constant: bool,
|
||||||
|
expr: Expr,
|
||||||
|
},
|
||||||
|
Expr(Expr),
|
||||||
|
Noop,
|
||||||
|
}
|
||||||
|
|
||||||
|
#[derive(Debug, Clone)]
|
||||||
|
pub enum Expr {
|
||||||
|
Unit,
|
||||||
|
Lit(Lit),
|
||||||
|
Sym(Rc<String>), //a Sym is anything that can be looked up by name at runtime - i.e. a function or variable address
|
||||||
|
Tuple(Vec<Expr>),
|
||||||
|
Func(Func),
|
||||||
|
Constructor {
|
||||||
|
type_name: Rc<String>,
|
||||||
|
name: Rc<String>,
|
||||||
|
tag: usize,
|
||||||
|
arity: usize, // n.b. arity here is always the value from the symbol table - if it doesn't match what it's being called with, that's an eval error, eval will handle it
|
||||||
|
},
|
||||||
|
Call {
|
||||||
|
f: Box<Expr>,
|
||||||
|
args: Vec<Expr>,
|
||||||
|
},
|
||||||
|
Assign {
|
||||||
|
val: Box<Expr>, //TODO this probably can't be a val
|
||||||
|
expr: Box<Expr>,
|
||||||
|
},
|
||||||
|
Conditional {
|
||||||
|
cond: Box<Expr>,
|
||||||
|
then_clause: Vec<Stmt>,
|
||||||
|
else_clause: Vec<Stmt>,
|
||||||
|
},
|
||||||
|
ConditionalTargetSigilValue,
|
||||||
|
CaseMatch {
|
||||||
|
cond: Box<Expr>,
|
||||||
|
alternatives: Vec<Alternative>,
|
||||||
|
},
|
||||||
|
UnimplementedSigilValue,
|
||||||
|
ReductionError(String),
|
||||||
|
}
|
||||||
|
|
||||||
|
pub type BoundVars = Vec<Option<Rc<String>>>; //remember that order matters here
|
||||||
|
|
||||||
|
#[derive(Debug, Clone)]
|
||||||
|
pub struct Alternative {
|
||||||
|
pub matchable: Subpattern,
|
||||||
|
pub item: Vec<Stmt>,
|
||||||
|
}
|
||||||
|
|
||||||
|
#[derive(Debug, Clone)]
|
||||||
|
pub struct Subpattern {
|
||||||
|
pub tag: Option<usize>,
|
||||||
|
pub subpatterns: Vec<Option<Subpattern>>,
|
||||||
|
pub bound_vars: BoundVars,
|
||||||
|
pub guard: Option<Expr>,
|
||||||
|
}
|
||||||
|
|
||||||
|
#[derive(Debug, Clone)]
|
||||||
|
pub enum Lit {
|
||||||
|
Nat(u64),
|
||||||
|
Int(i64),
|
||||||
|
Float(f64),
|
||||||
|
Bool(bool),
|
||||||
|
StringLit(Rc<String>),
|
||||||
|
}
|
||||||
|
|
||||||
|
#[derive(Debug, Clone)]
|
||||||
|
pub enum Func {
|
||||||
|
BuiltIn(Builtin),
|
||||||
|
UserDefined {
|
||||||
|
name: Option<Rc<String>>,
|
||||||
|
params: Vec<Rc<String>>,
|
||||||
|
body: Vec<Stmt>,
|
||||||
|
},
|
||||||
|
}
|
||||||
Loading…
Reference in New Issue
Block a user