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February 5, 2014 16:24
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CoffeeScript Grammar
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/* converted on Thu Feb 6, 2014, 00:09 (UTC+08) by jison-to-w3c v0.33.722 which is Copyright (c) 2011-2013 by Gunther Rademacher <[email protected]> */ | |
Root ::= Body? | |
Body ::= Line ( TERMINATOR Line | TERMINATOR )* | |
Line ::= Expression | |
| Statement | |
Statement | |
::= Return | |
| Comment | |
| STATEMENT | |
Expression | |
::= Value | |
| Invocation | |
| Code | |
| Operation | |
| Assign | |
| If | |
| Try | |
| While | |
| For | |
| Switch | |
| Class | |
| Throw | |
Block ::= INDENT OUTDENT | |
| INDENT Body OUTDENT | |
Identifier | |
::= IDENTIFIER | |
AlphaNumeric | |
::= NUMBER | |
| STRING | |
Literal ::= AlphaNumeric | |
| JS | |
| REGEX | |
| DEBUGGER | |
| UNDEFINED | |
| NULL | |
| BOOL | |
Assign ::= Assignable '=' Expression | |
| Assignable '=' TERMINATOR Expression | |
| Assignable '=' INDENT Expression OUTDENT | |
AssignObj | |
::= ObjAssignable | |
| ObjAssignable ':' Expression | |
| ObjAssignable ':' INDENT Expression OUTDENT | |
| Comment | |
ObjAssignable | |
::= Identifier | |
| AlphaNumeric | |
| ThisProperty | |
Return ::= RETURN Expression | |
| RETURN | |
Comment ::= HERECOMMENT | |
Code ::= PARAM_START ParamList PARAM_END FuncGlyph Block | |
| FuncGlyph Block | |
FuncGlyph | |
::= '->' | |
| '=>' | |
OptComma ::= ','? | |
ParamList | |
::= ( Param | ParamList ',' Param | ParamList OptComma TERMINATOR Param | ParamList OptComma INDENT ParamList OptComma OUTDENT )? | |
Param ::= ParamVar | |
| ParamVar '...' | |
| ParamVar '=' Expression | |
| '...' | |
ParamVar ::= Identifier | |
| ThisProperty | |
| Array | |
| Object | |
Splat ::= Expression '...' | |
SimpleAssignable | |
::= Identifier | |
| Value Accessor | |
| Invocation Accessor | |
| ThisProperty | |
Assignable | |
::= SimpleAssignable | |
| Array | |
| Object | |
Value ::= Assignable | |
| Literal | |
| Parenthetical | |
| Range | |
| This | |
Accessor ::= '.' Identifier | |
| '?.' Identifier | |
| '::' Identifier | |
| '?::' Identifier | |
| '::' | |
| INDEX_SOAK* INDEX_START IndexValue INDEX_END | |
IndexValue | |
::= Expression | |
| Slice | |
Object ::= '{' AssignList OptComma '}' | |
AssignList | |
::= ( AssignObj | AssignList ',' AssignObj | AssignList OptComma TERMINATOR AssignObj | AssignList OptComma INDENT AssignList OptComma OUTDENT )? | |
Class ::= CLASS | |
| CLASS Block | |
| CLASS EXTENDS Expression | |
| CLASS EXTENDS Expression Block | |
| CLASS SimpleAssignable | |
| CLASS SimpleAssignable Block | |
| CLASS SimpleAssignable EXTENDS Expression | |
| CLASS SimpleAssignable EXTENDS Expression Block | |
Invocation | |
::= ( Value OptFuncExist Arguments | SUPER | SUPER Arguments ) ( OptFuncExist Arguments )* | |
OptFuncExist | |
::= FUNC_EXIST? | |
Arguments | |
::= CALL_START CALL_END | |
| CALL_START ArgList OptComma CALL_END | |
This ::= THIS | |
| '@' | |
ThisProperty | |
::= '@' Identifier | |
Array ::= '[' ']' | |
| '[' ArgList OptComma ']' | |
RangeDots | |
::= '..' | |
| '...' | |
Range ::= '[' Expression RangeDots Expression ']' | |
Slice ::= Expression RangeDots Expression | |
| Expression RangeDots | |
| RangeDots Expression | |
| RangeDots | |
ArgList ::= Arg | |
| ArgList ',' Arg | |
| ArgList OptComma TERMINATOR Arg | |
| INDENT ArgList OptComma OUTDENT | |
| ArgList OptComma INDENT ArgList OptComma OUTDENT | |
Arg ::= Expression | |
| Splat | |
| '...' | |
SimpleArgs | |
::= Expression ( ',' Expression )* | |
Try ::= TRY Block | |
| TRY Block Catch | |
| TRY Block FINALLY Block | |
| TRY Block Catch FINALLY Block | |
Catch ::= CATCH Identifier Block | |
| CATCH Object Block | |
| CATCH Block | |
Throw ::= THROW Expression | |
Parenthetical | |
::= '(' Body ')' | |
| '(' INDENT Body OUTDENT ')' | |
WhileSource | |
::= WHILE Expression | |
| WHILE Expression WHEN Expression | |
| UNTIL Expression | |
| UNTIL Expression WHEN Expression | |
While ::= WhileSource Block | |
| Statement WhileSource | |
| Expression WhileSource | |
| Loop | |
Loop ::= LOOP Block | |
| LOOP Expression | |
For ::= Statement ForBody | |
| Expression ForBody | |
| ForBody Block | |
ForBody ::= FOR Range | |
| ForStart ForSource | |
ForStart ::= FOR ForVariables | |
| FOR OWN ForVariables | |
ForValue ::= Identifier | |
| ThisProperty | |
| Array | |
| Object | |
ForVariables | |
::= ForValue | |
| ForValue ',' ForValue | |
ForSource | |
::= FORIN Expression | |
| FOROF Expression | |
| FORIN Expression WHEN Expression | |
| FOROF Expression WHEN Expression | |
| FORIN Expression BY Expression | |
| FORIN Expression WHEN Expression BY Expression | |
| FORIN Expression BY Expression WHEN Expression | |
Switch ::= SWITCH Expression INDENT Whens OUTDENT | |
| SWITCH Expression INDENT Whens ELSE Block OUTDENT | |
| SWITCH INDENT Whens OUTDENT | |
| SWITCH INDENT Whens ELSE Block OUTDENT | |
Whens ::= When+ | |
When ::= LEADING_WHEN SimpleArgs Block | |
| LEADING_WHEN SimpleArgs Block TERMINATOR | |
IfBlock ::= IF Expression Block ( ELSE IF Expression Block )* | |
If ::= IfBlock | |
| IfBlock ELSE Block | |
| Statement POST_IF Expression | |
| Expression POST_IF Expression | |
Operation | |
::= UNARY Expression | |
| UNARY_MATH Expression | |
| '-' Expression | |
| '+' Expression | |
| '--' SimpleAssignable | |
| '++' SimpleAssignable | |
| SimpleAssignable '--' | |
| SimpleAssignable '++' | |
| Expression '?' | |
| Expression '+' Expression | |
| Expression '-' Expression | |
| Expression MATH Expression | |
| Expression '**' Expression | |
| Expression SHIFT Expression | |
| Expression COMPARE Expression | |
| Expression LOGIC Expression | |
| Expression RELATION Expression | |
| SimpleAssignable COMPOUND_ASSIGN Expression | |
| SimpleAssignable COMPOUND_ASSIGN INDENT Expression OUTDENT | |
| SimpleAssignable COMPOUND_ASSIGN TERMINATOR Expression | |
| SimpleAssignable EXTENDS Expression |
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# The CoffeeScript parser is generated by [Jison](http://github.com/zaach/jison) | |
# from this grammar file. Jison is a bottom-up parser generator, similar in | |
# style to [Bison](http://www.gnu.org/software/bison), implemented in JavaScript. | |
# It can recognize [LALR(1), LR(0), SLR(1), and LR(1)](http://en.wikipedia.org/wiki/LR_grammar) | |
# type grammars. To create the Jison parser, we list the pattern to match | |
# on the left-hand side, and the action to take (usually the creation of syntax | |
# tree nodes) on the right. As the parser runs, it | |
# shifts tokens from our token stream, from left to right, and | |
# [attempts to match](http://en.wikipedia.org/wiki/Bottom-up_parsing) | |
# the token sequence against the rules below. When a match can be made, it | |
# reduces into the [nonterminal](http://en.wikipedia.org/wiki/Terminal_and_nonterminal_symbols) | |
# (the enclosing name at the top), and we proceed from there. | |
# | |
# If you run the `cake build:parser` command, Jison constructs a parse table | |
# from our rules and saves it into `lib/parser.js`. | |
# The only dependency is on the **Jison.Parser**. | |
# {Parser} = require 'jison' | |
# Jison DSL | |
# --------- | |
# Since we're going to be wrapped in a function by Jison in any case, if our | |
# action immediately returns a value, we can optimize by removing the function | |
# wrapper and just returning the value directly. | |
unwrap = /^function\s*\(\)\s*\{\s*return\s*([\s\S]*);\s*\}/ | |
# Our handy DSL for Jison grammar generation, thanks to | |
# [Tim Caswell](http://github.com/creationix). For every rule in the grammar, | |
# we pass the pattern-defining string, the action to run, and extra options, | |
# optionally. If no action is specified, we simply pass the value of the | |
# previous nonterminal. | |
o = (patternString, action, options) -> | |
patternString = patternString.replace /\s{2,}/g, ' ' | |
patternCount = patternString.split(' ').length | |
return [patternString, '$$ = $1;', options] unless action | |
action = if match = unwrap.exec action then match[1] else "(#{action}())" | |
# All runtime functions we need are defined on "yy" | |
action = action.replace /\bnew /g, '$&yy.' | |
action = action.replace /\b(?:Block\.wrap|extend)\b/g, 'yy.$&' | |
# Returns a function which adds location data to the first parameter passed | |
# in, and returns the parameter. If the parameter is not a node, it will | |
# just be passed through unaffected. | |
addLocationDataFn = (first, last) -> | |
if not last | |
"yy.addLocationDataFn(@#{first})" | |
else | |
"yy.addLocationDataFn(@#{first}, @#{last})" | |
action = action.replace /LOC\(([0-9]*)\)/g, addLocationDataFn('$1') | |
action = action.replace /LOC\(([0-9]*),\s*([0-9]*)\)/g, addLocationDataFn('$1', '$2') | |
[patternString, "$$ = #{addLocationDataFn(1, patternCount)}(#{action});", options] | |
# Grammatical Rules | |
# ----------------- | |
# In all of the rules that follow, you'll see the name of the nonterminal as | |
# the key to a list of alternative matches. With each match's action, the | |
# dollar-sign variables are provided by Jison as references to the value of | |
# their numeric position, so in this rule: | |
# | |
# "Expression UNLESS Expression" | |
# | |
# `$1` would be the value of the first `Expression`, `$2` would be the token | |
# for the `UNLESS` terminal, and `$3` would be the value of the second | |
# `Expression`. | |
grammar = | |
# The **Root** is the top-level node in the syntax tree. Since we parse bottom-up, | |
# all parsing must end here. | |
Root: [ | |
o '', -> new Block | |
o 'Body' | |
] | |
# Any list of statements and expressions, separated by line breaks or semicolons. | |
Body: [ | |
o 'Line', -> Block.wrap [$1] | |
o 'Body TERMINATOR Line', -> $1.push $3 | |
o 'Body TERMINATOR' | |
] | |
# Block and statements, which make up a line in a body. | |
Line: [ | |
o 'Expression' | |
o 'Statement' | |
] | |
# Pure statements which cannot be expressions. | |
Statement: [ | |
o 'Return' | |
o 'Comment' | |
o 'STATEMENT', -> new Literal $1 | |
] | |
# All the different types of expressions in our language. The basic unit of | |
# CoffeeScript is the **Expression** -- everything that can be an expression | |
# is one. Blocks serve as the building blocks of many other rules, making | |
# them somewhat circular. | |
Expression: [ | |
o 'Value' | |
o 'Invocation' | |
o 'Code' | |
o 'Operation' | |
o 'Assign' | |
o 'If' | |
o 'Try' | |
o 'While' | |
o 'For' | |
o 'Switch' | |
o 'Class' | |
o 'Throw' | |
] | |
# An indented block of expressions. Note that the [Rewriter](rewriter.html) | |
# will convert some postfix forms into blocks for us, by adjusting the | |
# token stream. | |
Block: [ | |
o 'INDENT OUTDENT', -> new Block | |
o 'INDENT Body OUTDENT', -> $2 | |
] | |
# A literal identifier, a variable name or property. | |
Identifier: [ | |
o 'IDENTIFIER', -> new Literal $1 | |
] | |
# Alphanumerics are separated from the other **Literal** matchers because | |
# they can also serve as keys in object literals. | |
AlphaNumeric: [ | |
o 'NUMBER', -> new Literal $1 | |
o 'STRING', -> new Literal $1 | |
] | |
# All of our immediate values. Generally these can be passed straight | |
# through and printed to JavaScript. | |
Literal: [ | |
o 'AlphaNumeric' | |
o 'JS', -> new Literal $1 | |
o 'REGEX', -> new Literal $1 | |
o 'DEBUGGER', -> new Literal $1 | |
o 'UNDEFINED', -> new Undefined | |
o 'NULL', -> new Null | |
o 'BOOL', -> new Bool $1 | |
] | |
# Assignment of a variable, property, or index to a value. | |
Assign: [ | |
o 'Assignable = Expression', -> new Assign $1, $3 | |
o 'Assignable = TERMINATOR Expression', -> new Assign $1, $4 | |
o 'Assignable = INDENT Expression OUTDENT', -> new Assign $1, $4 | |
] | |
# Assignment when it happens within an object literal. The difference from | |
# the ordinary **Assign** is that these allow numbers and strings as keys. | |
AssignObj: [ | |
o 'ObjAssignable', -> new Value $1 | |
o 'ObjAssignable : Expression', -> new Assign LOC(1)(new Value($1)), $3, 'object' | |
o 'ObjAssignable : | |
INDENT Expression OUTDENT', -> new Assign LOC(1)(new Value($1)), $4, 'object' | |
o 'Comment' | |
] | |
ObjAssignable: [ | |
o 'Identifier' | |
o 'AlphaNumeric' | |
o 'ThisProperty' | |
] | |
# A return statement from a function body. | |
Return: [ | |
o 'RETURN Expression', -> new Return $2 | |
o 'RETURN', -> new Return | |
] | |
# A block comment. | |
Comment: [ | |
o 'HERECOMMENT', -> new Comment $1 | |
] | |
# The **Code** node is the function literal. It's defined by an indented block | |
# of **Block** preceded by a function arrow, with an optional parameter | |
# list. | |
Code: [ | |
o 'PARAM_START ParamList PARAM_END FuncGlyph Block', -> new Code $2, $5, $4 | |
o 'FuncGlyph Block', -> new Code [], $2, $1 | |
] | |
# CoffeeScript has two different symbols for functions. `->` is for ordinary | |
# functions, and `=>` is for functions bound to the current value of *this*. | |
FuncGlyph: [ | |
o '->', -> 'func' | |
o '=>', -> 'boundfunc' | |
] | |
# An optional, trailing comma. | |
OptComma: [ | |
o '' | |
o ',' | |
] | |
# The list of parameters that a function accepts can be of any length. | |
ParamList: [ | |
o '', -> [] | |
o 'Param', -> [$1] | |
o 'ParamList , Param', -> $1.concat $3 | |
o 'ParamList OptComma TERMINATOR Param', -> $1.concat $4 | |
o 'ParamList OptComma INDENT ParamList OptComma OUTDENT', -> $1.concat $4 | |
] | |
# A single parameter in a function definition can be ordinary, or a splat | |
# that hoovers up the remaining arguments. | |
Param: [ | |
o 'ParamVar', -> new Param $1 | |
o 'ParamVar ...', -> new Param $1, null, on | |
o 'ParamVar = Expression', -> new Param $1, $3 | |
o '...', -> new Expansion | |
] | |
# Function Parameters | |
ParamVar: [ | |
o 'Identifier' | |
o 'ThisProperty' | |
o 'Array' | |
o 'Object' | |
] | |
# A splat that occurs outside of a parameter list. | |
Splat: [ | |
o 'Expression ...', -> new Splat $1 | |
] | |
# Variables and properties that can be assigned to. | |
SimpleAssignable: [ | |
o 'Identifier', -> new Value $1 | |
o 'Value Accessor', -> $1.add $2 | |
o 'Invocation Accessor', -> new Value $1, [].concat $2 | |
o 'ThisProperty' | |
] | |
# Everything that can be assigned to. | |
Assignable: [ | |
o 'SimpleAssignable' | |
o 'Array', -> new Value $1 | |
o 'Object', -> new Value $1 | |
] | |
# The types of things that can be treated as values -- assigned to, invoked | |
# as functions, indexed into, named as a class, etc. | |
Value: [ | |
o 'Assignable' | |
o 'Literal', -> new Value $1 | |
o 'Parenthetical', -> new Value $1 | |
o 'Range', -> new Value $1 | |
o 'This' | |
] | |
# The general group of accessors into an object, by property, by prototype | |
# or by array index or slice. | |
Accessor: [ | |
o '. Identifier', -> new Access $2 | |
o '?. Identifier', -> new Access $2, 'soak' | |
o ':: Identifier', -> [LOC(1)(new Access new Literal('prototype')), LOC(2)(new Access $2)] | |
o '?:: Identifier', -> [LOC(1)(new Access new Literal('prototype'), 'soak'), LOC(2)(new Access $2)] | |
o '::', -> new Access new Literal 'prototype' | |
o 'Index' | |
] | |
# Indexing into an object or array using bracket notation. | |
Index: [ | |
o 'INDEX_START IndexValue INDEX_END', -> $2 | |
o 'INDEX_SOAK Index', -> extend $2, soak : yes | |
] | |
IndexValue: [ | |
o 'Expression', -> new Index $1 | |
o 'Slice', -> new Slice $1 | |
] | |
# In CoffeeScript, an object literal is simply a list of assignments. | |
Object: [ | |
o '{ AssignList OptComma }', -> new Obj $2, $1.generated | |
] | |
# Assignment of properties within an object literal can be separated by | |
# comma, as in JavaScript, or simply by newline. | |
AssignList: [ | |
o '', -> [] | |
o 'AssignObj', -> [$1] | |
o 'AssignList , AssignObj', -> $1.concat $3 | |
o 'AssignList OptComma TERMINATOR AssignObj', -> $1.concat $4 | |
o 'AssignList OptComma INDENT AssignList OptComma OUTDENT', -> $1.concat $4 | |
] | |
# Class definitions have optional bodies of prototype property assignments, | |
# and optional references to the superclass. | |
Class: [ | |
o 'CLASS', -> new Class | |
o 'CLASS Block', -> new Class null, null, $2 | |
o 'CLASS EXTENDS Expression', -> new Class null, $3 | |
o 'CLASS EXTENDS Expression Block', -> new Class null, $3, $4 | |
o 'CLASS SimpleAssignable', -> new Class $2 | |
o 'CLASS SimpleAssignable Block', -> new Class $2, null, $3 | |
o 'CLASS SimpleAssignable EXTENDS Expression', -> new Class $2, $4 | |
o 'CLASS SimpleAssignable EXTENDS Expression Block', -> new Class $2, $4, $5 | |
] | |
# Ordinary function invocation, or a chained series of calls. | |
Invocation: [ | |
o 'Value OptFuncExist Arguments', -> new Call $1, $3, $2 | |
o 'Invocation OptFuncExist Arguments', -> new Call $1, $3, $2 | |
o 'SUPER', -> new Call 'super', [new Splat new Literal 'arguments'] | |
o 'SUPER Arguments', -> new Call 'super', $2 | |
] | |
# An optional existence check on a function. | |
OptFuncExist: [ | |
o '', -> no | |
o 'FUNC_EXIST', -> yes | |
] | |
# The list of arguments to a function call. | |
Arguments: [ | |
o 'CALL_START CALL_END', -> [] | |
o 'CALL_START ArgList OptComma CALL_END', -> $2 | |
] | |
# A reference to the *this* current object. | |
This: [ | |
o 'THIS', -> new Value new Literal 'this' | |
o '@', -> new Value new Literal 'this' | |
] | |
# A reference to a property on *this*. | |
ThisProperty: [ | |
o '@ Identifier', -> new Value LOC(1)(new Literal('this')), [LOC(2)(new Access($2))], 'this' | |
] | |
# The array literal. | |
Array: [ | |
o '[ ]', -> new Arr [] | |
o '[ ArgList OptComma ]', -> new Arr $2 | |
] | |
# Inclusive and exclusive range dots. | |
RangeDots: [ | |
o '..', -> 'inclusive' | |
o '...', -> 'exclusive' | |
] | |
# The CoffeeScript range literal. | |
Range: [ | |
o '[ Expression RangeDots Expression ]', -> new Range $2, $4, $3 | |
] | |
# Array slice literals. | |
Slice: [ | |
o 'Expression RangeDots Expression', -> new Range $1, $3, $2 | |
o 'Expression RangeDots', -> new Range $1, null, $2 | |
o 'RangeDots Expression', -> new Range null, $2, $1 | |
o 'RangeDots', -> new Range null, null, $1 | |
] | |
# The **ArgList** is both the list of objects passed into a function call, | |
# as well as the contents of an array literal | |
# (i.e. comma-separated expressions). Newlines work as well. | |
ArgList: [ | |
o 'Arg', -> [$1] | |
o 'ArgList , Arg', -> $1.concat $3 | |
o 'ArgList OptComma TERMINATOR Arg', -> $1.concat $4 | |
o 'INDENT ArgList OptComma OUTDENT', -> $2 | |
o 'ArgList OptComma INDENT ArgList OptComma OUTDENT', -> $1.concat $4 | |
] | |
# Valid arguments are Blocks or Splats. | |
Arg: [ | |
o 'Expression' | |
o 'Splat' | |
o '...', -> new Expansion | |
] | |
# Just simple, comma-separated, required arguments (no fancy syntax). We need | |
# this to be separate from the **ArgList** for use in **Switch** blocks, where | |
# having the newlines wouldn't make sense. | |
SimpleArgs: [ | |
o 'Expression' | |
o 'SimpleArgs , Expression', -> [].concat $1, $3 | |
] | |
# The variants of *try/catch/finally* exception handling blocks. | |
Try: [ | |
o 'TRY Block', -> new Try $2 | |
o 'TRY Block Catch', -> new Try $2, $3[0], $3[1] | |
o 'TRY Block FINALLY Block', -> new Try $2, null, null, $4 | |
o 'TRY Block Catch FINALLY Block', -> new Try $2, $3[0], $3[1], $5 | |
] | |
# A catch clause names its error and runs a block of code. | |
Catch: [ | |
o 'CATCH Identifier Block', -> [$2, $3] | |
o 'CATCH Object Block', -> [LOC(2)(new Value($2)), $3] | |
o 'CATCH Block', -> [null, $2] | |
] | |
# Throw an exception object. | |
Throw: [ | |
o 'THROW Expression', -> new Throw $2 | |
] | |
# Parenthetical expressions. Note that the **Parenthetical** is a **Value**, | |
# not an **Expression**, so if you need to use an expression in a place | |
# where only values are accepted, wrapping it in parentheses will always do | |
# the trick. | |
Parenthetical: [ | |
o '( Body )', -> new Parens $2 | |
o '( INDENT Body OUTDENT )', -> new Parens $3 | |
] | |
# The condition portion of a while loop. | |
WhileSource: [ | |
o 'WHILE Expression', -> new While $2 | |
o 'WHILE Expression WHEN Expression', -> new While $2, guard: $4 | |
o 'UNTIL Expression', -> new While $2, invert: true | |
o 'UNTIL Expression WHEN Expression', -> new While $2, invert: true, guard: $4 | |
] | |
# The while loop can either be normal, with a block of expressions to execute, | |
# or postfix, with a single expression. There is no do..while. | |
While: [ | |
o 'WhileSource Block', -> $1.addBody $2 | |
o 'Statement WhileSource', -> $2.addBody LOC(1) Block.wrap([$1]) | |
o 'Expression WhileSource', -> $2.addBody LOC(1) Block.wrap([$1]) | |
o 'Loop', -> $1 | |
] | |
Loop: [ | |
o 'LOOP Block', -> new While(LOC(1) new Literal 'true').addBody $2 | |
o 'LOOP Expression', -> new While(LOC(1) new Literal 'true').addBody LOC(2) Block.wrap [$2] | |
] | |
# Array, object, and range comprehensions, at the most generic level. | |
# Comprehensions can either be normal, with a block of expressions to execute, | |
# or postfix, with a single expression. | |
For: [ | |
o 'Statement ForBody', -> new For $1, $2 | |
o 'Expression ForBody', -> new For $1, $2 | |
o 'ForBody Block', -> new For $2, $1 | |
] | |
ForBody: [ | |
o 'FOR Range', -> source: LOC(2) new Value($2) | |
o 'ForStart ForSource', -> $2.own = $1.own; $2.name = $1[0]; $2.index = $1[1]; $2 | |
] | |
ForStart: [ | |
o 'FOR ForVariables', -> $2 | |
o 'FOR OWN ForVariables', -> $3.own = yes; $3 | |
] | |
# An array of all accepted values for a variable inside the loop. | |
# This enables support for pattern matching. | |
ForValue: [ | |
o 'Identifier' | |
o 'ThisProperty' | |
o 'Array', -> new Value $1 | |
o 'Object', -> new Value $1 | |
] | |
# An array or range comprehension has variables for the current element | |
# and (optional) reference to the current index. Or, *key, value*, in the case | |
# of object comprehensions. | |
ForVariables: [ | |
o 'ForValue', -> [$1] | |
o 'ForValue , ForValue', -> [$1, $3] | |
] | |
# The source of a comprehension is an array or object with an optional guard | |
# clause. If it's an array comprehension, you can also choose to step through | |
# in fixed-size increments. | |
ForSource: [ | |
o 'FORIN Expression', -> source: $2 | |
o 'FOROF Expression', -> source: $2, object: yes | |
o 'FORIN Expression WHEN Expression', -> source: $2, guard: $4 | |
o 'FOROF Expression WHEN Expression', -> source: $2, guard: $4, object: yes | |
o 'FORIN Expression BY Expression', -> source: $2, step: $4 | |
o 'FORIN Expression WHEN Expression BY Expression', -> source: $2, guard: $4, step: $6 | |
o 'FORIN Expression BY Expression WHEN Expression', -> source: $2, step: $4, guard: $6 | |
] | |
Switch: [ | |
o 'SWITCH Expression INDENT Whens OUTDENT', -> new Switch $2, $4 | |
o 'SWITCH Expression INDENT Whens ELSE Block OUTDENT', -> new Switch $2, $4, $6 | |
o 'SWITCH INDENT Whens OUTDENT', -> new Switch null, $3 | |
o 'SWITCH INDENT Whens ELSE Block OUTDENT', -> new Switch null, $3, $5 | |
] | |
Whens: [ | |
o 'When' | |
o 'Whens When', -> $1.concat $2 | |
] | |
# An individual **When** clause, with action. | |
When: [ | |
o 'LEADING_WHEN SimpleArgs Block', -> [[$2, $3]] | |
o 'LEADING_WHEN SimpleArgs Block TERMINATOR', -> [[$2, $3]] | |
] | |
# The most basic form of *if* is a condition and an action. The following | |
# if-related rules are broken up along these lines in order to avoid | |
# ambiguity. | |
IfBlock: [ | |
o 'IF Expression Block', -> new If $2, $3, type: $1 | |
o 'IfBlock ELSE IF Expression Block', -> $1.addElse LOC(3,5) new If $4, $5, type: $3 | |
] | |
# The full complement of *if* expressions, including postfix one-liner | |
# *if* and *unless*. | |
If: [ | |
o 'IfBlock' | |
o 'IfBlock ELSE Block', -> $1.addElse $3 | |
o 'Statement POST_IF Expression', -> new If $3, LOC(1)(Block.wrap [$1]), type: $2, statement: true | |
o 'Expression POST_IF Expression', -> new If $3, LOC(1)(Block.wrap [$1]), type: $2, statement: true | |
] | |
# Arithmetic and logical operators, working on one or more operands. | |
# Here they are grouped by order of precedence. The actual precedence rules | |
# are defined at the bottom of the page. It would be shorter if we could | |
# combine most of these rules into a single generic *Operand OpSymbol Operand* | |
# -type rule, but in order to make the precedence binding possible, separate | |
# rules are necessary. | |
Operation: [ | |
o 'UNARY Expression', -> new Op $1 , $2 | |
o 'UNARY_MATH Expression', -> new Op $1 , $2 | |
o '- Expression', (-> new Op '-', $2), prec: 'UNARY_MATH' | |
o '+ Expression', (-> new Op '+', $2), prec: 'UNARY_MATH' | |
o '-- SimpleAssignable', -> new Op '--', $2 | |
o '++ SimpleAssignable', -> new Op '++', $2 | |
o 'SimpleAssignable --', -> new Op '--', $1, null, true | |
o 'SimpleAssignable ++', -> new Op '++', $1, null, true | |
# [The existential operator](http://jashkenas.github.com/coffee-script/#existence). | |
o 'Expression ?', -> new Existence $1 | |
o 'Expression + Expression', -> new Op '+' , $1, $3 | |
o 'Expression - Expression', -> new Op '-' , $1, $3 | |
o 'Expression MATH Expression', -> new Op $2, $1, $3 | |
o 'Expression ** Expression', -> new Op $2, $1, $3 | |
o 'Expression SHIFT Expression', -> new Op $2, $1, $3 | |
o 'Expression COMPARE Expression', -> new Op $2, $1, $3 | |
o 'Expression LOGIC Expression', -> new Op $2, $1, $3 | |
o 'Expression RELATION Expression', -> | |
if $2.charAt(0) is '!' | |
new Op($2[1..], $1, $3).invert() | |
else | |
new Op $2, $1, $3 | |
o 'SimpleAssignable COMPOUND_ASSIGN | |
Expression', -> new Assign $1, $3, $2 | |
o 'SimpleAssignable COMPOUND_ASSIGN | |
INDENT Expression OUTDENT', -> new Assign $1, $4, $2 | |
o 'SimpleAssignable COMPOUND_ASSIGN TERMINATOR | |
Expression', -> new Assign $1, $4, $2 | |
o 'SimpleAssignable EXTENDS Expression', -> new Extends $1, $3 | |
] | |
# Precedence | |
# ---------- | |
# Operators at the top of this list have higher precedence than the ones lower | |
# down. Following these rules is what makes `2 + 3 * 4` parse as: | |
# | |
# 2 + (3 * 4) | |
# | |
# And not: | |
# | |
# (2 + 3) * 4 | |
operators = [ | |
['left', '.', '?.', '::', '?::'] | |
['left', 'CALL_START', 'CALL_END'] | |
['nonassoc', '++', '--'] | |
['left', '?'] | |
['right', 'UNARY'] | |
['right', '**'] | |
['right', 'UNARY_MATH'] | |
['left', 'MATH'] | |
['left', '+', '-'] | |
['left', 'SHIFT'] | |
['left', 'RELATION'] | |
['left', 'COMPARE'] | |
['left', 'LOGIC'] | |
['nonassoc', 'INDENT', 'OUTDENT'] | |
['right', '=', ':', 'COMPOUND_ASSIGN', 'RETURN', 'THROW', 'EXTENDS'] | |
['right', 'FORIN', 'FOROF', 'BY', 'WHEN'] | |
['right', 'IF', 'ELSE', 'FOR', 'WHILE', 'UNTIL', 'LOOP', 'SUPER', 'CLASS'] | |
['left', 'POST_IF'] | |
] | |
# Wrapping Up | |
# ----------- | |
# Finally, now that we have our **grammar** and our **operators**, we can create | |
# our **Jison.Parser**. We do this by processing all of our rules, recording all | |
# terminals (every symbol which does not appear as the name of a rule above) | |
# as "tokens". | |
tokens = [] | |
for name, alternatives of grammar | |
grammar[name] = for alt in alternatives | |
for token in alt[0].split ' ' | |
tokens.push token unless grammar[token] | |
alt[1] = "return #{alt[1]}" if name is 'Root' | |
alt | |
# Initialize the **Parser** with our list of terminal **tokens**, our **grammar** | |
# rules, and the name of the root. Reverse the operators because Jison orders | |
# precedence from low to high, and we have it high to low | |
# (as in [Yacc](http://dinosaur.compilertools.net/yacc/index.html)). | |
#exports.parser = new Parser | |
console.log JSON.stringify | |
tokens : tokens.join ' ' | |
bnf : grammar | |
operators : operators.reverse() | |
startSymbol : 'Root' |
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