bloodyroots

re_quote = require('regexp-quote') inspect_orig = require('util').inspect inspect = (x) -> inspect_orig(x, false, null) require('sprintf.js') typeIsArray = Array.isArray || ( value ) -> return {}.toString.call( value ) is '[object Array]' class Parser @define_production: (alpha_s, beta) -> @prototype[alpha_s] = (vdata, idx) -> beta.op.call this, vdata, idx @define_grammar_operation: (name, op_f) -> this[name] = (args...) -> { name: name, op: if op_f? then op_f.apply this, args else this['match_' + name].apply this, args } @define_grammar_operation 'at_least_one', (beta, suffix) -> @match_range(beta, 1, undefined, true, suffix) @define_grammar_operation 'alternation' @define_grammar_operation 'range' @define_grammar_operation 're', (re_str, match_name) -> @match_re(RegExp('^(?:' + re_str + ')'), match_name) @define_grammar_operation 'seq' @define_grammar_operation 'transform', (f, beta) -> @op_transform(f, beta) @define_grammar_operation 'v' @define_grammar_operation 'var_re' @define_grammar_operation 'zero_or_more', (beta, suffix) -> @match_range(beta, 0, undefined, true, suffix) @define_grammar_operation 'zero_or_one', (beta, suffix) -> @match_range(beta, 0, 1, true, suffix) @backref: (ref) -> (vdata) -> m = /^([^\[]*)\[([0-9]*)\]/.exec(ref) [ (vdata[m[1]] || [ ])[m[2]], ] debug_log: (f) -> if @constructor.debug [ name, idx, outcome, data ] = f.call(this) '%-15s %3s %-25s %-8s %s\n'.printf name, idx, @string_abbrev(idx, 25), outcome || '', data || '' @match_alternation: (args...) -> if typeIsArray args[0] [ beta_seq, suffix ] = args else beta_seq = args (vdata, idx) -> @debug_log -> [ 'alternation', idx, 'begin', 'alternation=%s%s'.sprintf (beta.name for beta in beta_seq), (if suffix? then ' suffix='+suffix.name else ' no-suffix') ] i = 0 for beta in beta_seq @debug_log -> [ 'alternation', idx, 'i='+i, beta.name ] m = beta.op.call this, vdata, idx if m? if suffix? m2 = suffix.op.call this, vdata, idx + m[0] if m2? @debug_log -> [ 'alternation', idx + m[0] + m2[0], 'success', 'count='+(i+1) ] return [ m[0] + m2[0], { pos: idx, length: m[0] + m2[0], type: 'seq', seq: [ m[1], m2[1] ] } ] else @debug_log -> [ 'alternation', idx + m[0], 'success', 'count=%d'.sprintf (i+1) ] return m i++ @debug_log -> [ 'alternation', idx, 'fail' ] return @match_range: (beta, min=0, max, greedy=true, suffix) -> if greedy @_match_greedy_range(beta, min, max, suffix) else @_match_nongreedy_range(beta, min, max, suffix) @_match_greedy_range: (beta, min, max, suffix) -> (vdata, idx) -> return unless state = @_match_range_to_min(beta, min, max, true, vdata, idx) match_indices = [ state.progress ] @_match_range_from_min beta, max, vdata, idx, state, => match_indices.push(state.progress) false while match_indices.length state.progress = match_indices.pop() @debug_log -> [ 'range', idx + state.progress, 'i='+state.count, 'greedy backtracking' ] return result if result = @_match_range_suffix(suffix, vdata, idx, state) state.work.pop() state.count-- @debug_log -> [ 'range', idx + state.progress, 'fail', 'greedy backtracking' ] return @_match_nongreedy_range: (beta, min, max, suffix) -> (vdata, idx) -> return unless state = @_match_range_to_min(beta, min, max, false, vdata, idx) @_match_range_suffix(suffix, vdata, idx, state) or @_match_range_from_min(beta, max, vdata, idx, state, => @_match_range_suffix(suffix, vdata, idx, state) ) or (@debug_log( -> [ 'range', idx + state.progress, 'fail', '>=min non-greedy' ]); undefined) _match_range_to_min: (beta, min, max, greedy, vdata, idx) -> @debug_log -> [ 'range', idx, 'begin', '%s min=%s max=%s %s %s'.sprintf(beta.name, min, (if max? then max else ''), (if greedy then 'greedy' else 'non-greedy'), (if suffix? then 'suffix='+suffix.name else 'no-suffix')) ] if max? and min > max @debug_log -> [ 're', idx, 'fail', 'min > max' ] return state = { count: 0, progress: 0, work: [], greedy: greedy } while state.count < min @debug_log -> [ 'range', idx + state.progress, 'i='+state.count, '<min' ] m = beta.op.call this, vdata, idx + state.progress unless m? @debug_log -> [ 'range', idx + state.progress, 'fail', '<min matches' ] return state.progress += m[0] state.work.push m[1] state.count++ state _match_range_from_min: (beta, max, vdata, idx, state, func) -> while not max? or state.count < max @debug_log -> [ 'range', idx + state.progress, 'i='+state.count, '>=min %s'.sprintf(if state.greedy then 'greedy' else 'non-greedy') ] m = beta.op.call this, vdata, idx + state.progress break unless m? state.progress += m[0] state.work.push m[1] state.count++ if output = func() return output return _match_range_suffix: (suffix, vdata, idx, state) -> if suffix? if (m = suffix.op.call this, vdata, idx + state.progress)? state.progress += m[0] state.work.push m[1] @debug_log -> [ 'range', idx + state.progress, 'success', 'count=%d %s'.sprintf(state.count, (if state.greedy then 'greedy' else 'non-greedy')) ] return [ state.progress, { pos: idx, length: state.progress, type: 'seq', seq: state.work } ] else return else @debug_log -> [ 'range', idx + state.progress, 'success', 'count=%d %s'.sprintf(state.count, (if state.greedy then 'greedy' else 'non-greedy trivial')) ] return [ state.progress, { pos: idx, length: state.progress, type: 'seq', seq: state.work } ] @match_re: (rre, match_name) -> (vdata, idx) -> m = rre.exec @str.substr idx if m @debug_log -> [ 're', idx, 'success', @strip_quotes inspect rre.source ] vdata[match_name] = m[0..-1] if match_name? [ m[0].length, { pos: idx, length: m[0].length, type: 're', match: m[0], groups: m[0..-1] } ] else @debug_log -> [ 're', idx, 'fail', @strip_quotes inspect rre.source ] return @match_seq: (beta_seq...) -> (vdata, idx) -> @debug_log -> [ 'seq', idx, 'begin', (beta.name for beta in beta_seq) ] progress = 0 work = [ ] i = 0 for beta in beta_seq @debug_log -> [ 'seq', idx + progress, 'i='+i, beta.name ] m = beta.op.call this, vdata, idx + progress unless m? @debug_log -> [ 'seq', idx + progress, 'fail' ] return progress += m[0] work.push m[1] i++ @debug_log -> [ 'seq', idx + progress, 'success' ] [ progress, { pos: idx, length: progress, type: 'seq', seq: work } ] @match_v: (alpha_s, argf) -> (vdata, idx) -> @debug_log -> [ 'v', idx, 'begin', alpha_s ] new_vdata = { } new_vdata.arg = argf.call this, vdata if argf? m = @vcache(alpha_s, idx, new_vdata) @debug_log -> [ 'v', idx + (if m? then m[0] else 0), (if m? then 'success' else 'fail'), alpha_s ] m @match_var_re: (re_str, match_name) -> self = this (vdata, idx) -> self.match_re(RegExp('^(?:' + @replace_backreferences(re_str, vdata) + ')'), match_name).call this, vdata, idx @op_transform: (f, beta) -> (vdata, idx) -> @debug_log -> [ 'transform', idx, 'begin', beta.name ] m = beta.op.call this, vdata, idx unless m? @debug_log -> [ 'transform', idx, 'fail', beta.name ] return tm = f.call this, m[1], vdata, idx unless tm? @debug_log -> [ 'transform', idx + m[0], 'fail', 'transform' ] return @debug_log -> [ 'transform', idx + m[0], 'success' ] [ m[0], tm ] parse: (str) -> @str = str @v_cache = {} @debug_log -> [ 'parse', 0, 'begin' ] doc = @Document { }, 0 unless doc? @debug_log -> [ 'parse', 0, 'fail' ] return @debug_log -> [ 'parse', doc[0], 'success' ] doc[1] replace_backreferences: (re_str, vdata) -> work = re_str while m = (/\\=([^\[]+)\[([0-9]+)\]/.exec(work)) mstr = (vdata[m[1]] || [ ])[m[2]] mstr ?= '' work = work.substr(0, m.index) + re_quote(mstr) + work.substr(m.index + m[0].length) work string_abbrev: (start, n) -> istr = @str.substr(start) istr = @strip_quotes inspect istr if istr.length > n istr.substr(0, n - 3) + '...' else istr strip_quotes: (str) -> m = /^'(.*)'$/.exec(str) if m m[1] else str vcache: (alpha_s, idx, vdata) -> cache_key = [ alpha_s, idx, JSON.stringify(vdata) ].join('#') if @v_cache.hasOwnProperty(cache_key) @debug_log -> [ 'vcache', idx, 'cached' ] return @v_cache[cache_key] else @v_cache[cache_key] = this[alpha_s] vdata, idx exports.Parser = Parser