a 'runtime' parsing expression grammar parser
npm install caffeine-eightCome to C8 because you want an elegant, declarative API that makes parsing as easy as humanly possible. Stay for super powers like detailed parsing errors, predictable PEG-based parsing and runtime parser extendability.
Unlike other parsing libraries, CaffeineEight is not a parser-generator. There is no build step. Just extend a class, add some rules and you are ready to parse. With CaffeineEight you can create and, more importantly, extend your parsers at runtime.
#### Motivating Example
A complete JSON parser in less than 30 lines of code.
``coffeescriptCaffeineScript
class JsonParser extends &CaffeineEight.Parser
@rule
root: :array :object
array:
"'[' _? ']'"
"'[' _? value commaValue* _? ']'"
object:
"'{' _? '}'"
"'{' _? pair commaPair* _? '}'"
commaValue: "_? ',' _? value"
commaPair: "_? ',' _? pair"
pair: "string _? ':' _? value"
value: :object :array :number :string :true :false :null
string: /"(?:[^"\\]|\\(?:["\\\/bfnrt]|u[0-9a-fA-F]{4}))*"/
number: /-?(?:0|[1-9]\d*)(?:\.\d+)?(?:[eE][+-]?\d+)?/
true: /true/
false: /false/
null: /null/
_: /\ +/
.repl()
``
* Define PEG parsers 100% in JavaScript
* Runtime-extensible parsers
* Reasonably fast
* No globals - each parser instance parses in its own space
* Full parsing expression grammar support with memoizing
* Full JavaScript regular expressions support for terminals
* Simple, convention-over-configuration parse-tree class structure
* Human-readable parse-tree dumps
* Detailed information about parsing failures
* Custom sub-parser hooks
* Which enable indention-based block parsing for languages like Python, CoffeeScript, or my own CaffeineScript
* CaffeineEight was formally called BabelBridgeJs
* CaffeineEight was inspired by my earlier Babel Bridge Ruby Gem, the JavaScript version turned out to be even more awesome!