Emotibars

Here's a grammar off the top of my head. Feel free to challenge this if you think something's wrong. I won't be checking for insane edge-cases that are hidden in here. For instance I don't think this explains how backticks work, but that sounds like a lot of work.

emotibars
  = (string lodid)* string
  = (string openblock emotistatement closeblock)* string

closeblock
  = yay _ blocktype _ yay

openblock
  = ohnoes _ blocktype _ id _ ohnoes

lodid
  = openlod id closelod
  = lod

blocktype
  = if|unless|each

backtick
  = `

yay
  = \\o/

ohnoes
  = /o\\

lod
  = \u0CA0_\u0CA0

closelod
  = _\u0CA0

openlod
  = \u0CA0_

string
  = _ (_ chars _)*

id
  = [a-zA-Z$_][^ \t\n\r,.+={}]*

chars
  = char+

char
  = [^{}\\\0-\x1F\x7f \t\n\r]

digits
  = [0-9]+

hexDigit
  = [0-9a-fA-F]

_ "whitespace"
  = whitespace*

whitespace
  = [ \t\n\r]

Examples

emotibars('My name is ಠ_ಠ.', 'alex');
> My name is alex.

emotibars('My name is ಠ_name_ಠ.', {name: 'alex'});
> My name is alex.

emotibars('Our names are: /o\\each names/o\\\n  - ಠ_ಠ\\o/each\\o/', ['alex', 'michelle', 'batman']);
> Our names are:
  - alex
  - michelle
  - batman

emotibars('My name is `ಠ_name`_ಠ.');
> My name is ಠ_name_ಠ.

emotibars('My name is ``ಠ_name_ಠ.', {name: 'alex'});
> My name is `alex.

Program API

emotibars(template, data)
// returns the rendered template

emotibars.parse(template)
// returns an AST

emotibars.compile(AST)
// returns an executable javascript function that:
// - takes one argument (the data passed to the template)
// - returns the rendered template

// optional:
emotibars.precompile(template)
// returns the string representation of the function expected from emotibars.compile

General rules

No compile to js
No parser-generators
Error messages are important (parse and run-time)
Document your code

Where I'll run

(All latest)

node
chrome
firefox

Prize

A print of this XKCD comic signed by Randall Munroe