diff options
Diffstat (limited to 'jni/ruby/lib/racc')
| -rw-r--r-- | jni/ruby/lib/racc/parser.rb | 622 | ||||
| -rw-r--r-- | jni/ruby/lib/racc/rdoc/grammar.en.rdoc | 219 |
2 files changed, 841 insertions, 0 deletions
diff --git a/jni/ruby/lib/racc/parser.rb b/jni/ruby/lib/racc/parser.rb new file mode 100644 index 0000000..f811ab6 --- /dev/null +++ b/jni/ruby/lib/racc/parser.rb @@ -0,0 +1,622 @@ +#-- +# $originalId: parser.rb,v 1.8 2006/07/06 11:42:07 aamine Exp $ +# +# Copyright (c) 1999-2006 Minero Aoki +# +# This program is free software. +# You can distribute/modify this program under the same terms of ruby. +# +# As a special exception, when this code is copied by Racc +# into a Racc output file, you may use that output file +# without restriction. +#++ + +module Racc + class ParseError < StandardError; end +end +unless defined?(::ParseError) + ParseError = Racc::ParseError +end + +# Racc is a LALR(1) parser generator. +# It is written in Ruby itself, and generates Ruby programs. +# +# == Command-line Reference +# +# racc [-o<var>filename</var>] [--output-file=<var>filename</var>] +# [-e<var>rubypath</var>] [--embedded=<var>rubypath</var>] +# [-v] [--verbose] +# [-O<var>filename</var>] [--log-file=<var>filename</var>] +# [-g] [--debug] +# [-E] [--embedded] +# [-l] [--no-line-convert] +# [-c] [--line-convert-all] +# [-a] [--no-omit-actions] +# [-C] [--check-only] +# [-S] [--output-status] +# [--version] [--copyright] [--help] <var>grammarfile</var> +# +# [+filename+] +# Racc grammar file. Any extension is permitted. +# [-o+outfile+, --output-file=+outfile+] +# A filename for output. default is <+filename+>.tab.rb +# [-O+filename+, --log-file=+filename+] +# Place logging output in file +filename+. +# Default log file name is <+filename+>.output. +# [-e+rubypath+, --executable=+rubypath+] +# output executable file(mode 755). where +path+ is the Ruby interpreter. +# [-v, --verbose] +# verbose mode. create +filename+.output file, like yacc's y.output file. +# [-g, --debug] +# add debug code to parser class. To display debugging information, +# use this '-g' option and set @yydebug true in parser class. +# [-E, --embedded] +# Output parser which doesn't need runtime files (racc/parser.rb). +# [-C, --check-only] +# Check syntax of racc grammar file and quit. +# [-S, --output-status] +# Print messages time to time while compiling. +# [-l, --no-line-convert] +# turns off line number converting. +# [-c, --line-convert-all] +# Convert line number of actions, inner, header and footer. +# [-a, --no-omit-actions] +# Call all actions, even if an action is empty. +# [--version] +# print Racc version and quit. +# [--copyright] +# Print copyright and quit. +# [--help] +# Print usage and quit. +# +# == Generating Parser Using Racc +# +# To compile Racc grammar file, simply type: +# +# $ racc parse.y +# +# This creates Ruby script file "parse.tab.y". The -o option can change the output filename. +# +# == Writing A Racc Grammar File +# +# If you want your own parser, you have to write a grammar file. +# A grammar file contains the name of your parser class, grammar for the parser, +# user code, and anything else. +# When writing a grammar file, yacc's knowledge is helpful. +# If you have not used yacc before, Racc is not too difficult. +# +# Here's an example Racc grammar file. +# +# class Calcparser +# rule +# target: exp { print val[0] } +# +# exp: exp '+' exp +# | exp '*' exp +# | '(' exp ')' +# | NUMBER +# end +# +# Racc grammar files resemble yacc files. +# But (of course), this is Ruby code. +# yacc's $$ is the 'result', $0, $1... is +# an array called 'val', and $-1, $-2... is an array called '_values'. +# +# See the {Grammar File Reference}[rdoc-ref:lib/racc/rdoc/grammar.en.rdoc] for +# more information on grammar files. +# +# == Parser +# +# Then you must prepare the parse entry method. There are two types of +# parse methods in Racc, Racc::Parser#do_parse and Racc::Parser#yyparse +# +# Racc::Parser#do_parse is simple. +# +# It's yyparse() of yacc, and Racc::Parser#next_token is yylex(). +# This method must returns an array like [TOKENSYMBOL, ITS_VALUE]. +# EOF is [false, false]. +# (TOKENSYMBOL is a Ruby symbol (taken from String#intern) by default. +# If you want to change this, see the grammar reference. +# +# Racc::Parser#yyparse is little complicated, but useful. +# It does not use Racc::Parser#next_token, instead it gets tokens from any iterator. +# +# For example, <code>yyparse(obj, :scan)</code> causes +# calling +obj#scan+, and you can return tokens by yielding them from +obj#scan+. +# +# == Debugging +# +# When debugging, "-v" or/and the "-g" option is helpful. +# +# "-v" creates verbose log file (.output). +# "-g" creates a "Verbose Parser". +# Verbose Parser prints the internal status when parsing. +# But it's _not_ automatic. +# You must use -g option and set +@yydebug+ to +true+ in order to get output. +# -g option only creates the verbose parser. +# +# === Racc reported syntax error. +# +# Isn't there too many "end"? +# grammar of racc file is changed in v0.10. +# +# Racc does not use '%' mark, while yacc uses huge number of '%' marks.. +# +# === Racc reported "XXXX conflicts". +# +# Try "racc -v xxxx.y". +# It causes producing racc's internal log file, xxxx.output. +# +# === Generated parsers does not work correctly +# +# Try "racc -g xxxx.y". +# This command let racc generate "debugging parser". +# Then set @yydebug=true in your parser. +# It produces a working log of your parser. +# +# == Re-distributing Racc runtime +# +# A parser, which is created by Racc, requires the Racc runtime module; +# racc/parser.rb. +# +# Ruby 1.8.x comes with Racc runtime module, +# you need NOT distribute Racc runtime files. +# +# If you want to include the Racc runtime module with your parser. +# This can be done by using '-E' option: +# +# $ racc -E -omyparser.rb myparser.y +# +# This command creates myparser.rb which `includes' Racc runtime. +# Only you must do is to distribute your parser file (myparser.rb). +# +# Note: parser.rb is LGPL, but your parser is not. +# Your own parser is completely yours. +module Racc + + unless defined?(Racc_No_Extensions) + Racc_No_Extensions = false # :nodoc: + end + + class Parser + + Racc_Runtime_Version = '1.4.6' + Racc_Runtime_Revision = %w$originalRevision: 1.8 $[1] + + Racc_Runtime_Core_Version_R = '1.4.6' + Racc_Runtime_Core_Revision_R = %w$originalRevision: 1.8 $[1] + begin + require 'racc/cparse' + # Racc_Runtime_Core_Version_C = (defined in extension) + Racc_Runtime_Core_Revision_C = Racc_Runtime_Core_Id_C.split[2] + unless new.respond_to?(:_racc_do_parse_c, true) + raise LoadError, 'old cparse.so' + end + if Racc_No_Extensions + raise LoadError, 'selecting ruby version of racc runtime core' + end + + Racc_Main_Parsing_Routine = :_racc_do_parse_c # :nodoc: + Racc_YY_Parse_Method = :_racc_yyparse_c # :nodoc: + Racc_Runtime_Core_Version = Racc_Runtime_Core_Version_C # :nodoc: + Racc_Runtime_Core_Revision = Racc_Runtime_Core_Revision_C # :nodoc: + Racc_Runtime_Type = 'c' # :nodoc: + rescue LoadError + Racc_Main_Parsing_Routine = :_racc_do_parse_rb + Racc_YY_Parse_Method = :_racc_yyparse_rb + Racc_Runtime_Core_Version = Racc_Runtime_Core_Version_R + Racc_Runtime_Core_Revision = Racc_Runtime_Core_Revision_R + Racc_Runtime_Type = 'ruby' + end + + def Parser.racc_runtime_type # :nodoc: + Racc_Runtime_Type + end + + def _racc_setup + @yydebug = false unless self.class::Racc_debug_parser + @yydebug = false unless defined?(@yydebug) + if @yydebug + @racc_debug_out = $stderr unless defined?(@racc_debug_out) + @racc_debug_out ||= $stderr + end + arg = self.class::Racc_arg + arg[13] = true if arg.size < 14 + arg + end + + def _racc_init_sysvars + @racc_state = [0] + @racc_tstack = [] + @racc_vstack = [] + + @racc_t = nil + @racc_val = nil + + @racc_read_next = true + + @racc_user_yyerror = false + @racc_error_status = 0 + end + + # The entry point of the parser. This method is used with #next_token. + # If Racc wants to get token (and its value), calls next_token. + # + # Example: + # def parse + # @q = [[1,1], + # [2,2], + # [3,3], + # [false, '$']] + # do_parse + # end + # + # def next_token + # @q.shift + # end + def do_parse + __send__(Racc_Main_Parsing_Routine, _racc_setup(), false) + end + + # The method to fetch next token. + # If you use #do_parse method, you must implement #next_token. + # + # The format of return value is [TOKEN_SYMBOL, VALUE]. + # +token-symbol+ is represented by Ruby's symbol by default, e.g. :IDENT + # for 'IDENT'. ";" (String) for ';'. + # + # The final symbol (End of file) must be false. + def next_token + raise NotImplementedError, "#{self.class}\#next_token is not defined" + end + + def _racc_do_parse_rb(arg, in_debug) + action_table, action_check, action_default, action_pointer, + _, _, _, _, + _, _, token_table, _, + _, _, * = arg + + _racc_init_sysvars + tok = act = i = nil + + catch(:racc_end_parse) { + while true + if i = action_pointer[@racc_state[-1]] + if @racc_read_next + if @racc_t != 0 # not EOF + tok, @racc_val = next_token() + unless tok # EOF + @racc_t = 0 + else + @racc_t = (token_table[tok] or 1) # error token + end + racc_read_token(@racc_t, tok, @racc_val) if @yydebug + @racc_read_next = false + end + end + i += @racc_t + unless i >= 0 and + act = action_table[i] and + action_check[i] == @racc_state[-1] + act = action_default[@racc_state[-1]] + end + else + act = action_default[@racc_state[-1]] + end + while act = _racc_evalact(act, arg) + ; + end + end + } + end + + # Another entry point for the parser. + # If you use this method, you must implement RECEIVER#METHOD_ID method. + # + # RECEIVER#METHOD_ID is a method to get next token. + # It must 'yield' the token, which format is [TOKEN-SYMBOL, VALUE]. + def yyparse(recv, mid) + __send__(Racc_YY_Parse_Method, recv, mid, _racc_setup(), true) + end + + def _racc_yyparse_rb(recv, mid, arg, c_debug) + action_table, action_check, action_default, action_pointer, + _, _, _, _, + _, _, token_table, _, + _, _, * = arg + + _racc_init_sysvars + act = nil + i = nil + + catch(:racc_end_parse) { + until i = action_pointer[@racc_state[-1]] + while act = _racc_evalact(action_default[@racc_state[-1]], arg) + ; + end + end + recv.__send__(mid) do |tok, val| + unless tok + @racc_t = 0 + else + @racc_t = (token_table[tok] or 1) # error token + end + @racc_val = val + @racc_read_next = false + + i += @racc_t + unless i >= 0 and + act = action_table[i] and + action_check[i] == @racc_state[-1] + act = action_default[@racc_state[-1]] + end + while act = _racc_evalact(act, arg) + ; + end + + while not(i = action_pointer[@racc_state[-1]]) or + not @racc_read_next or + @racc_t == 0 # $ + unless i and i += @racc_t and + i >= 0 and + act = action_table[i] and + action_check[i] == @racc_state[-1] + act = action_default[@racc_state[-1]] + end + while act = _racc_evalact(act, arg) + ; + end + end + end + } + end + + ### + ### common + ### + + def _racc_evalact(act, arg) + action_table, action_check, _, action_pointer, + _, _, _, _, + _, _, _, shift_n, reduce_n, + _, _, * = arg + + if act > 0 and act < shift_n + # + # shift + # + if @racc_error_status > 0 + @racc_error_status -= 1 unless @racc_t == 1 # error token + end + @racc_vstack.push @racc_val + @racc_state.push act + @racc_read_next = true + if @yydebug + @racc_tstack.push @racc_t + racc_shift @racc_t, @racc_tstack, @racc_vstack + end + + elsif act < 0 and act > -reduce_n + # + # reduce + # + code = catch(:racc_jump) { + @racc_state.push _racc_do_reduce(arg, act) + false + } + if code + case code + when 1 # yyerror + @racc_user_yyerror = true # user_yyerror + return -reduce_n + when 2 # yyaccept + return shift_n + else + raise '[Racc Bug] unknown jump code' + end + end + + elsif act == shift_n + # + # accept + # + racc_accept if @yydebug + throw :racc_end_parse, @racc_vstack[0] + + elsif act == -reduce_n + # + # error + # + case @racc_error_status + when 0 + unless arg[21] # user_yyerror + on_error @racc_t, @racc_val, @racc_vstack + end + when 3 + if @racc_t == 0 # is $ + throw :racc_end_parse, nil + end + @racc_read_next = true + end + @racc_user_yyerror = false + @racc_error_status = 3 + while true + if i = action_pointer[@racc_state[-1]] + i += 1 # error token + if i >= 0 and + (act = action_table[i]) and + action_check[i] == @racc_state[-1] + break + end + end + throw :racc_end_parse, nil if @racc_state.size <= 1 + @racc_state.pop + @racc_vstack.pop + if @yydebug + @racc_tstack.pop + racc_e_pop @racc_state, @racc_tstack, @racc_vstack + end + end + return act + + else + raise "[Racc Bug] unknown action #{act.inspect}" + end + + racc_next_state(@racc_state[-1], @racc_state) if @yydebug + + nil + end + + def _racc_do_reduce(arg, act) + _, _, _, _, + goto_table, goto_check, goto_default, goto_pointer, + nt_base, reduce_table, _, _, + _, use_result, * = arg + state = @racc_state + vstack = @racc_vstack + tstack = @racc_tstack + + i = act * -3 + len = reduce_table[i] + reduce_to = reduce_table[i+1] + method_id = reduce_table[i+2] + void_array = [] + + tmp_t = tstack[-len, len] if @yydebug + tmp_v = vstack[-len, len] + tstack[-len, len] = void_array if @yydebug + vstack[-len, len] = void_array + state[-len, len] = void_array + + # tstack must be updated AFTER method call + if use_result + vstack.push __send__(method_id, tmp_v, vstack, tmp_v[0]) + else + vstack.push __send__(method_id, tmp_v, vstack) + end + tstack.push reduce_to + + racc_reduce(tmp_t, reduce_to, tstack, vstack) if @yydebug + + k1 = reduce_to - nt_base + if i = goto_pointer[k1] + i += state[-1] + if i >= 0 and (curstate = goto_table[i]) and goto_check[i] == k1 + return curstate + end + end + goto_default[k1] + end + + # This method is called when a parse error is found. + # + # ERROR_TOKEN_ID is an internal ID of token which caused error. + # You can get string representation of this ID by calling + # #token_to_str. + # + # ERROR_VALUE is a value of error token. + # + # value_stack is a stack of symbol values. + # DO NOT MODIFY this object. + # + # This method raises ParseError by default. + # + # If this method returns, parsers enter "error recovering mode". + def on_error(t, val, vstack) + raise ParseError, sprintf("\nparse error on value %s (%s)", + val.inspect, token_to_str(t) || '?') + end + + # Enter error recovering mode. + # This method does not call #on_error. + def yyerror + throw :racc_jump, 1 + end + + # Exit parser. + # Return value is Symbol_Value_Stack[0]. + def yyaccept + throw :racc_jump, 2 + end + + # Leave error recovering mode. + def yyerrok + @racc_error_status = 0 + end + + # For debugging output + def racc_read_token(t, tok, val) + @racc_debug_out.print 'read ' + @racc_debug_out.print tok.inspect, '(', racc_token2str(t), ') ' + @racc_debug_out.puts val.inspect + @racc_debug_out.puts + end + + def racc_shift(tok, tstack, vstack) + @racc_debug_out.puts "shift #{racc_token2str tok}" + racc_print_stacks tstack, vstack + @racc_debug_out.puts + end + + def racc_reduce(toks, sim, tstack, vstack) + out = @racc_debug_out + out.print 'reduce ' + if toks.empty? + out.print ' <none>' + else + toks.each {|t| out.print ' ', racc_token2str(t) } + end + out.puts " --> #{racc_token2str(sim)}" + + racc_print_stacks tstack, vstack + @racc_debug_out.puts + end + + def racc_accept + @racc_debug_out.puts 'accept' + @racc_debug_out.puts + end + + def racc_e_pop(state, tstack, vstack) + @racc_debug_out.puts 'error recovering mode: pop token' + racc_print_states state + racc_print_stacks tstack, vstack + @racc_debug_out.puts + end + + def racc_next_state(curstate, state) + @racc_debug_out.puts "goto #{curstate}" + racc_print_states state + @racc_debug_out.puts + end + + def racc_print_stacks(t, v) + out = @racc_debug_out + out.print ' [' + t.each_index do |i| + out.print ' (', racc_token2str(t[i]), ' ', v[i].inspect, ')' + end + out.puts ' ]' + end + + def racc_print_states(s) + out = @racc_debug_out + out.print ' [' + s.each {|st| out.print ' ', st } + out.puts ' ]' + end + + def racc_token2str(tok) + self.class::Racc_token_to_s_table[tok] or + raise "[Racc Bug] can't convert token #{tok} to string" + end + + # Convert internal ID of token symbol to the string. + def token_to_str(t) + self.class::Racc_token_to_s_table[t] + end + + end + +end diff --git a/jni/ruby/lib/racc/rdoc/grammar.en.rdoc b/jni/ruby/lib/racc/rdoc/grammar.en.rdoc new file mode 100644 index 0000000..a154246 --- /dev/null +++ b/jni/ruby/lib/racc/rdoc/grammar.en.rdoc @@ -0,0 +1,219 @@ += Racc Grammar File Reference + +== Global Structure + +== Class Block and User Code Block + +There are two blocks on toplevel. One is 'class' block, another is 'user code' +block. 'user code' block MUST be placed after 'class' block. + +== Comments + +You can insert comments about all places. Two style comments can be used, Ruby style '#.....' and C style '/\*......*\/'. + +== Class Block + +The class block is formed like this: + + class CLASS_NAME + [precedance table] + [token declarations] + [expected number of S/R conflicts] + [options] + [semantic value convertion] + [start rule] + rule + GRAMMARS + +CLASS_NAME is a name of parser class. This is the name of generating parser +class. + +If CLASS_NAME includes '::', Racc outputs module clause. For example, writing +"class M::C" causes creating the code bellow: + + module M + class C + : + : + end + end + +== Grammar Block + +The grammar block describes grammar which is able to be understood by parser. +Syntax is: + + (token): (token) (token) (token).... (action) + + (token): (token) (token) (token).... (action) + | (token) (token) (token).... (action) + | (token) (token) (token).... (action) + +(action) is an action which is executed when its (token)s are found. +(action) is a ruby code block, which is surrounded by braces: + + { print val[0] + puts val[1] } + +Note that you cannot use '%' string, here document, '%r' regexp in action. + +Actions can be omitted. When it is omitted, '' (empty string) is used. + +A return value of action is a value of left side value ($$). It is value of +result, or returned value by `return` statement. + +Here is an example of whole grammar block. + + rule + goal: definition rules source { result = val } + + definition: /* none */ { result = [] } + | definition startdesig { result[0] = val[1] } + | definition + precrule # this line continues from upper line + { + result[1] = val[1] + } + + startdesig: START TOKEN + +You can use the following special local variables in action: + +* result ($$) + +The value of left-hand side (lhs). A default value is val[0]. + +* val ($1,$2,$3...) + +An array of value of right-hand side (rhs). + +* _values (...$-2,$-1,$0) + +A stack of values. DO NOT MODIFY this stack unless you know what you are doing. + +== Operator Precedence + +This function is equal to '%prec' in yacc. +To designate this block: + + prechigh + nonassoc '++' + left '*' '/' + left '+' '-' + right '=' + preclow + +`right` is yacc's %right, `left` is yacc's %left. + +`=` + (symbol) means yacc's %prec: + + prechigh + nonassoc UMINUS + left '*' '/' + left '+' '-' + preclow + + rule + exp: exp '*' exp + | exp '-' exp + | '-' exp =UMINUS # equals to "%prec UMINUS" + : + : + +== expect + +Racc has bison's "expect" directive. + + # Example + + class MyParser + rule + expect 3 + : + : + +This directive declares "expected" number of shift/reduce conflicts. If +"expected" number is equal to real number of conflicts, Racc does not print +conflict warning message. + +== Declaring Tokens + +By declaring tokens, you can avoid many meaningless bugs. If declared token +does not exist or existing token does not decleared, Racc output warnings. +Declaration syntax is: + + token TOKEN_NAME AND_IS_THIS + ALSO_THIS_IS AGAIN_AND_AGAIN THIS_IS_LAST + +== Options + +You can write options for Racc command in your Racc file. + + options OPTION OPTION ... + +Options are: + +* omit_action_call + +omits empty action call or not. + +* result_var + +uses local variable "result" or not. + +You can use 'no_' prefix to invert their meanings. + +== Converting Token Symbol + +Token symbols are, as default, + + * naked token string in Racc file (TOK, XFILE, this_is_token, ...) + --> symbol (:TOK, :XFILE, :this_is_token, ...) + * quoted string (':', '.', '(', ...) + --> same string (':', '.', '(', ...) + +You can change this default by "convert" block. +Here is an example: + + convert + PLUS 'PlusClass' # We use PlusClass for symbol of `PLUS' + MIN 'MinusClass' # We use MinusClass for symbol of `MIN' + end + +We can use almost all ruby value can be used by token symbol, +except 'false' and 'nil'. These cause unexpected parse error. + +If you want to use String as token symbol, special care is required. +For example: + + convert + class '"cls"' # in code, "cls" + PLUS '"plus\n"' # in code, "plus\n" + MIN "\"minus#{val}\"" # in code, \"minus#{val}\" + end + +== Start Rule + +'%start' in yacc. This changes start rule. + + start real_target + +== User Code Block + +"User Code Block" is a Ruby source code which is copied to output. There are +three user code blocks, "header" "inner" and "footer". + +Format of user code is like this: + + ---- header + ruby statement + ruby statement + ruby statement + + ---- inner + ruby statement + : + : + +If four '-' exist on line head, Racc treat it as beginning of user code block. +The name of user code block must be one word. |