gridtracker/package.nw/lib/CLDRPluralRuleParser.js

686 wiersze
14 KiB
JavaScript

/* eslint-disable no-tabs */
/**
* cldrpluralparser.js
* A parser engine for CLDR plural rules.
*
* Copyright 2012-2014 Santhosh Thottingal and other contributors
* Released under the MIT license
* http://opensource.org/licenses/MIT
*
* @source https://github.com/santhoshtr/CLDRPluralRuleParser
* @author Santhosh Thottingal <santhosh.thottingal@gmail.com>
* @author Timo Tijhof
* @author Amir Aharoni
*/
/**
* Evaluates a plural rule in CLDR syntax for a number
* @param {string} rule
* @param {integer} number
* @return {boolean} true if evaluation passed, false if evaluation failed.
*/
// UMD returnExports https://github.com/umdjs/umd/blob/master/returnExports.js
(function(root, factory)
{
if (typeof define === "function" && define.amd)
{
// AMD. Register as an anonymous module.
define(factory);
}
else if (typeof exports === "object")
{
// Node. Does not work with strict CommonJS, but
// only CommonJS-like environments that support module.exports,
// like Node.
module.exports = factory();
}
else
{
// Browser globals (root is window)
root.pluralRuleParser = factory();
}
}(this, function()
{
function pluralRuleParser(rule, number)
{
"use strict";
/*
Syntax: see http://unicode.org/reports/tr35/#Language_Plural_Rules
-----------------------------------------------------------------
condition = and_condition ('or' and_condition)*
('@integer' samples)?
('@decimal' samples)?
and_condition = relation ('and' relation)*
relation = is_relation | in_relation | within_relation
is_relation = expr 'is' ('not')? value
in_relation = expr (('not')? 'in' | '=' | '!=') range_list
within_relation = expr ('not')? 'within' range_list
expr = operand (('mod' | '%') value)?
operand = 'n' | 'i' | 'f' | 't' | 'v' | 'w'
range_list = (range | value) (',' range_list)*
value = digit+
digit = 0|1|2|3|4|5|6|7|8|9
range = value'..'value
samples = sampleRange (',' sampleRange)* (',' ('…'|'...'))?
sampleRange = decimalValue '~' decimalValue
decimalValue = value ('.' value)?
*/
// We don't evaluate the samples section of the rule. Ignore it.
rule = rule.split("@")[0].replace(/^\s*/, "").replace(/\s*$/, "");
if (!rule.length)
{
// Empty rule or 'other' rule.
return true;
}
// Indicates the current position in the rule as we parse through it.
// Shared among all parsing functions below.
var pos = 0,
operand,
expression,
relation,
result,
whitespace = makeRegexParser(/^\s+/),
value = makeRegexParser(/^\d+/),
_n_ = makeStringParser("n"),
_i_ = makeStringParser("i"),
_f_ = makeStringParser("f"),
_t_ = makeStringParser("t"),
_v_ = makeStringParser("v"),
_w_ = makeStringParser("w"),
_is_ = makeStringParser("is"),
_isnot_ = makeStringParser("is not"),
_isnot_sign_ = makeStringParser("!="),
_equal_ = makeStringParser("="),
_mod_ = makeStringParser("mod"),
_percent_ = makeStringParser("%"),
_not_ = makeStringParser("not"),
_in_ = makeStringParser("in"),
_within_ = makeStringParser("within"),
_range_ = makeStringParser(".."),
_comma_ = makeStringParser(","),
_or_ = makeStringParser("or"),
_and_ = makeStringParser("and");
function debug()
{
// console.log.apply(console, arguments);
}
debug("pluralRuleParser", rule, number);
// Try parsers until one works, if none work return null
function choice(parserSyntax)
{
return function()
{
var i, result;
for (i = 0; i < parserSyntax.length; i++)
{
result = parserSyntax[i]();
if (result !== null)
{
return result;
}
}
return null;
};
}
// Try several parserSyntax-es in a row.
// All must succeed; otherwise, return null.
// This is the only eager one.
function sequence(parserSyntax)
{
var i, parserRes,
originalPos = pos,
result = [];
for (i = 0; i < parserSyntax.length; i++)
{
parserRes = parserSyntax[i]();
if (parserRes === null)
{
pos = originalPos;
return null;
}
result.push(parserRes);
}
return result;
}
// Run the same parser over and over until it fails.
// Must succeed a minimum of n times; otherwise, return null.
function nOrMore(n, p)
{
return function()
{
var originalPos = pos,
result = [],
parsed = p();
while (parsed !== null)
{
result.push(parsed);
parsed = p();
}
if (result.length < n)
{
pos = originalPos;
return null;
}
return result;
};
}
// Helpers - just make parserSyntax out of simpler JS builtin types
function makeStringParser(s)
{
var len = s.length;
return function()
{
var result = null;
if (rule.substr(pos, len) === s)
{
result = s;
pos += len;
}
return result;
};
}
function makeRegexParser(regex)
{
return function()
{
var matches = rule.substr(pos).match(regex);
if (matches === null)
{
return null;
}
pos += matches[0].length;
return matches[0];
};
}
/**
* Integer digits of n.
*/
function i()
{
var result = _i_();
if (result === null)
{
debug(" -- failed i", parseInt(number, 10));
return result;
}
result = parseInt(number, 10);
debug(" -- passed i ", result);
return result;
}
/**
* Absolute value of the source number (integer and decimals).
*/
function n()
{
var result = _n_();
if (result === null)
{
debug(" -- failed n ", number);
return result;
}
result = parseFloat(number, 10);
debug(" -- passed n ", result);
return result;
}
/**
* Visible fractional digits in n, with trailing zeros.
*/
function f()
{
var result = _f_();
if (result === null)
{
debug(" -- failed f ", number);
return result;
}
result = (number + ".").split(".")[1] || 0;
debug(" -- passed f ", result);
return result;
}
/**
* Visible fractional digits in n, without trailing zeros.
*/
function t()
{
var result = _t_();
if (result === null)
{
debug(" -- failed t ", number);
return result;
}
result = (number + ".").split(".")[1].replace(/0$/, "") || 0;
debug(" -- passed t ", result);
return result;
}
/**
* Number of visible fraction digits in n, with trailing zeros.
*/
function v()
{
var result = _v_();
if (result === null)
{
debug(" -- failed v ", number);
return result;
}
result = (number + ".").split(".")[1].length || 0;
debug(" -- passed v ", result);
return result;
}
/**
* Number of visible fraction digits in n, without trailing zeros.
*/
function w()
{
var result = _w_();
if (result === null)
{
debug(" -- failed w ", number);
return result;
}
result = (number + ".").split(".")[1].replace(/0$/, "").length || 0;
debug(" -- passed w ", result);
return result;
}
// operand = 'n' | 'i' | 'f' | 't' | 'v' | 'w'
operand = choice([n, i, f, t, v, w]);
// expr = operand (('mod' | '%') value)?
expression = choice([mod, operand]);
function mod()
{
var result = sequence(
[operand, whitespace, choice([_mod_, _percent_]), whitespace, value]
);
if (result === null)
{
debug(" -- failed mod");
return null;
}
debug(" -- passed " + parseInt(result[0], 10) + " " + result[2] + " " + parseInt(result[4], 10));
return parseFloat(result[0]) % parseInt(result[4], 10);
}
function not()
{
var result = sequence([whitespace, _not_]);
if (result === null)
{
debug(" -- failed not");
return null;
}
return result[1];
}
// is_relation = expr 'is' ('not')? value
function is()
{
var result = sequence([expression, whitespace, choice([_is_]), whitespace, value]);
if (result !== null)
{
debug(" -- passed is : " + result[0] + " == " + parseInt(result[4], 10));
return result[0] === parseInt(result[4], 10);
}
debug(" -- failed is");
return null;
}
// is_relation = expr 'is' ('not')? value
function isnot()
{
var result = sequence(
[expression, whitespace, choice([_isnot_, _isnot_sign_]), whitespace, value]
);
if (result !== null)
{
debug(" -- passed isnot: " + result[0] + " != " + parseInt(result[4], 10));
return result[0] !== parseInt(result[4], 10);
}
debug(" -- failed isnot");
return null;
}
function not_in()
{
var i, range_list,
result = sequence([expression, whitespace, _isnot_sign_, whitespace, rangeList]);
if (result !== null)
{
debug(" -- passed not_in: " + result[0] + " != " + result[4]);
range_list = result[4];
for (i = 0; i < range_list.length; i++)
{
if (parseInt(range_list[i], 10) === parseInt(result[0], 10))
{
return false;
}
}
return true;
}
debug(" -- failed not_in");
return null;
}
// range_list = (range | value) (',' range_list)*
function rangeList()
{
var result = sequence([choice([range, value]), nOrMore(0, rangeTail)]),
resultList = [];
if (result !== null)
{
resultList = resultList.concat(result[0]);
if (result[1][0])
{
resultList = resultList.concat(result[1][0]);
}
return resultList;
}
debug(" -- failed rangeList");
return null;
}
function rangeTail()
{
// ',' range_list
var result = sequence([_comma_, rangeList]);
if (result !== null)
{
return result[1];
}
debug(" -- failed rangeTail");
return null;
}
// range = value'..'value
function range()
{
var i, array, left, right,
result = sequence([value, _range_, value]);
if (result !== null)
{
debug(" -- passed range");
array = [];
left = parseInt(result[0], 10);
right = parseInt(result[2], 10);
for (i = left; i <= right; i++)
{
array.push(i);
}
return array;
}
debug(" -- failed range");
return null;
}
function _in()
{
var result, range_list, i;
// in_relation = expr ('not')? 'in' range_list
result = sequence(
[expression, nOrMore(0, not), whitespace, choice([_in_, _equal_]), whitespace, rangeList]
);
if (result !== null)
{
debug(" -- passed _in:" + result);
range_list = result[5];
for (i = 0; i < range_list.length; i++)
{
if (parseInt(range_list[i], 10) === parseFloat(result[0]))
{
return (result[1][0] !== "not");
}
}
return (result[1][0] === "not");
}
debug(" -- failed _in ");
return null;
}
/**
* The difference between "in" and "within" is that
* "in" only includes integers in the specified range,
* while "within" includes all values.
*/
function within()
{
var range_list, result;
// within_relation = expr ('not')? 'within' range_list
result = sequence(
[expression, nOrMore(0, not), whitespace, _within_, whitespace, rangeList]
);
if (result !== null)
{
debug(" -- passed within");
range_list = result[5];
if ((result[0] >= parseInt(range_list[0], 10)) &&
(result[0] < parseInt(range_list[range_list.length - 1], 10)))
{
return (result[1][0] !== "not");
}
return (result[1][0] === "not");
}
debug(" -- failed within ");
return null;
}
// relation = is_relation | in_relation | within_relation
relation = choice([is, not_in, isnot, _in, within]);
// and_condition = relation ('and' relation)*
function and()
{
var i,
result = sequence([relation, nOrMore(0, andTail)]);
if (result)
{
if (!result[0])
{
return false;
}
for (i = 0; i < result[1].length; i++)
{
if (!result[1][i])
{
return false;
}
}
return true;
}
debug(" -- failed and");
return null;
}
// ('and' relation)*
function andTail()
{
var result = sequence([whitespace, _and_, whitespace, relation]);
if (result !== null)
{
debug(" -- passed andTail" + result);
return result[3];
}
debug(" -- failed andTail");
return null;
}
// ('or' and_condition)*
function orTail()
{
var result = sequence([whitespace, _or_, whitespace, and]);
if (result !== null)
{
debug(" -- passed orTail: " + result[3]);
return result[3];
}
debug(" -- failed orTail");
return null;
}
// condition = and_condition ('or' and_condition)*
function condition()
{
var i,
result = sequence([and, nOrMore(0, orTail)]);
if (result)
{
for (i = 0; i < result[1].length; i++)
{
if (result[1][i])
{
return true;
}
}
return result[0];
}
return false;
}
result = condition();
/**
* For success, the pos must have gotten to the end of the rule
* and returned a non-null.
* n.b. This is part of language infrastructure,
* so we do not throw an internationalizable message.
*/
if (result === null)
{
throw new Error("Parse error at position " + pos.toString() + " for rule: " + rule);
}
if (pos !== rule.length)
{
debug("Warning: Rule not parsed completely. Parser stopped at " + rule.substr(0, pos) + " for rule: " + rule);
}
return result;
}
return pluralRuleParser;
}));