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Ragel is a finite-state machine compiler with output support for C, C++, C#, Objective-C, D, Java, OCaml, Go, and Ruby source code.〔 Adrian D. Thurston. "(Parsing Computer Languages with an Automaton Compiled from a Single Regular Expression. )" In: ''11th International Conference on Implementation and Application of Automata (CIAA 2006), Lecture Notes in Computer Science, volume 4094'', p. 285-286, Taipei, Taiwan, August 2006.〕 It supports the generation of table or control flow driven state machines from regular expressions〔Liqun Chen, Chris J. Mitchell, Andrew Martin (2009) ''Trusted Computing: Second International Conference, Trust 2009 Oxford, UK, April 6-8, 2009, Proceedings''. p. 111〕 and/or state charts and can also build lexical analysers via the longest-match method. Ragel specifically targets text parsing and input validation.〔Omar Badreddin (2010) "Umple: a model-oriented programming language." ''Software Engineering, 2010 ACM/IEEE 32nd International Conference on. Vol. 2''. IEEE, 2010.〕 == Overview == Ragel supports the generation of table or control flow driven state machines from regular expressions and/or state charts and can also build lexical analysers via the longest-match method. A unique feature of Ragel is that user actions can be associated with arbitrary state machine transitions using operators that are integrated into the regular expressions. Ragel also supports visualization of the generated machine via graphviz. File:Ragel visualisation.png The graph represents a state-machine that takes user input as a series of bytes representing ASCII characters and control codes. 48..57 is equivalent to the regular expression () (i.e. any digit), so only sequences beginning with a digit can be recognised. If 10 (line feed) is encountered, we're done. 46 is the decimal point ('.'), 43 and 45 are positive and negative signs ('+', '-') and 69/101 is uppercase/lowercase 'e' (to indicate a number in scientific format). As such it will recognize the following properly: 2 but not: .3 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Ragel」の詳細全文を読む スポンサード リンク
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