bubble-to-pegjs.rb first attempt

Author: steveyen

.gitignore

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+tmp

Makefile

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+all:
+	./sql-bubble.rb > tmp/rules.rb
+	./bubble-to-pegjs.rb tmp/rules.rb > tmp/sql.pegjs

bubble-to-pegjs.rb

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+#!/usr/bin/env ruby
+
+$keywords = {}
+
+def rule(name, *rest)
+  print "#{name} =\n"
+  rest.flatten.each do |x|
+    $keywords[x] = true if x.class == String and x.match(/^[A-Z]+$/)
+    print "#{x} "
+  end
+  print "\n\n"
+end
+
+def either(*rest)
+  r = []
+  rest.each {|x| r << x; r << '/' }
+  ["("] + r[0..-2] + [")"]
+end
+
+def stack(*rest)
+  return rest if rest.length <= 1
+  return ["("] + rest + [")"]
+end
+
+def line(*rest)
+  return stack(*rest)
+end
+
+def loop(*rest)
+  return ["("] + rest + [")+"]
+end
+
+def toploop(*rest)
+  return loop(*rest)
+end
+
+def tailbranch(*rest)
+  return rest
+end
+
+def opt(*rest)
+  return [rest, "?"] if rest.length <= 1
+  return ["("] + rest + [")?"]
+end
+
+def optx(*rest)
+  return opt(*rest)
+end
+
+# ----------------------------------------
+
+print "// generated pegjs\n"
+print "\n"
+print "start = sql_stmt_list\n"
+print "\n"
+
+grammar = ARGV[0]
+
+load grammar
+
+# ----------------------------------------
+
+print """
+dot = '.'
+comma = ','
+semicolon = ';'
+minusminus = '--'
+minus = '-'
+plus = '+'
+lparen = '('
+rparen = ')'
+star = '*'
+newline = '\\n'
+anything_except_newline = [^\\n]*
+comment_beg = '/*'
+comment_end = '*/'
+anything_except_comment_end = .* & '*/'
+whitespace = [ \\t]*
+nil = ''
+"""
+
+print "\n"
+
+$keywords.keys.sort.each do |keyword|
+  print "#{keyword} = whitespace \"#{keyword}\"\n"
+end
+