notes
-----

- parse arguments and store in recipe
- parse lines into fragments and store in recipe
- positional error messages

j: 
- vector of substitutions
  point to start, end, and &str which is name of variable
- also add a vector of substitutions
- indent for line continuation
- multiple names for short names are actually kind of nice
- multiple {{}} per line
- single assignment variables
- matched /{{.*?}}.*/ then unmatched /{{.*/
- echo subbed line
- static errors when variables are missing {{}}, even if recipe isn't run
- ignore comment lines
- post to facebook to get beta testers
- j user email list (how to engage users more generally?)
- see if dotbot guy likes it
- advertise on facebook to get users

- get the extracted script and test its structure
- can I add rust docs for the command/binary?
- change name to "a polyglot command runner"
- comment code
- fix docs (note that shell is invoked with -cu, explain -c and -u)
- publish to github and cargo
- spam facebook, reddit

- duplicate argument test
- should duplicate dependency mention recipe?
- get rid of panics

- doc comments on recipes
- in depth usage string with doc comments, args, dependencies

get rid of unused public items
tokenize error returns successfully parsed tokens
tokenize continues after parse error but inserts parse error into token stream
make sure regexes are only compiled once
fix grammar.txt to reflect reality

- create a really long example justfile
  . unzip tarball
  . update package manager deps
  . clean
  . update logs (repetitive git flow)

- full documentation
  . habit of using clever commands and writing little scripts
  . very low friction to write a script (no new file, chmod, add to rcs)
  . make list of contributors, include travis

variable setting
variable substitution:  {{}}
command line arguments: must be specified in recipe 'a foo bar:'
quote

arguments are subbed in with {{variable_name}}
doesn't conflict with shell syntax
doesn't conflict with jquery
conflicts a little bit with rust, but can be overcome
very common in many template languages

different ways of setting arguments:

- go for something like python, so we can use full python at the top level
- go for something like rust, so we can use rust at the top level
- don't do barewords, we need strings anyways, so parse them
- x = 10
- export x = 10
- export x

wishlist:
- ability to export environment variables
- preludes:
  may be nice to allow all recipes in a given langauge to share
  functions, variables, etc. could have a "prelude" recipe
  which was included as a prefix to other recipes
- windows support: currently calling 'sh', which won't work on windows
- args can be passed after --, or with some special syntax:
  a: 1 2 3 :
- should also add an annotation for recipes
  a FOO BAR, export variables FOO and BAR with args
  fail if doesn't get two arguments
- indent for line continuation
- use launch recipes asyncronously
- ~/.justfile: 
  . is this for non-project specific commands, so that when you
    type .j in any directory, it uses it as a justfile?
  . or is it for commands which are useful across projects?
- super complex recipe lines:
  a: b c # run b and c, then a
  b | a: c # run c, then b, and pipe output of b into a
  a >> a.log: # run a and append output to a.log
  a B C: # a takes B and C as command line args, like j a HELLO BOB
         # can enforce at command line
- what is the story for allowing justfiles in subdirectories?
  use a different name, like 'subjustfile' or 'jfile'.
  recurse up to the justfile, but add recipes in any jfile
  that you find along the way. recipes in justfile are accessible,
  and run from the justfile dir. recipes in jfile are run from jfile
  dir. refuse to run if a recipe in justfile and jfile conflict
- rust is a given, so one option is to write a very simple shell
  command parser and use that instead of the system shell. this
  would make recipes work across systems with incompatible shells.
  additionally, we could also define a mode where it will only call
  commands from cargo, which would make recipes work across systems
  with incompatible userlands 'rc' or 'cargo cult' is a great name