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:Sort of. In computing, it's a little more specific, though, referring to functions that call themselves as part of their normal running. This in turn has led to the idea of recursive definitions, that of course refer to the original word. Example: "recursion: see recursion." | :Sort of. In computing, it's a little more specific, though, referring to functions that call themselves as part of their normal running. This in turn has led to the idea of recursive definitions, that of course refer to the original word. Example: "recursion: see recursion." | ||
β | :I take issue with the explanation for another reason, though. True, regexes probably can't be used to check the validity of EBNFs. It's a little bit more complicated than that, though. If one has ever used a compiler-compiler like yacc (which, supposedly uses EBNF grammars or EBNF-like grammars), another tool in the Unix world comes to mind, awk. Awk is similar enough in design to a cc that it can do the job of one, and people have apparently made compilers in awk. And what does awk use for its pattern matching? Regexes | + | :I take issue with the explanation for another reason, though. True, regexes probably can't be used to check the validity of EBNFs. It's a little bit more complicated than that, though. If one has ever used a compiler-compiler like yacc (which, supposedly uses EBNF grammars or EBNF-like grammars), another tool in the Unix world comes to mind, awk. Awk is similar enough in design to a cc that it can do the job of one, and people have apparently made compilers in awk. And what does awk use for its pattern matching? Regexes. [[User:Tibfulv|Tibfulv]] ([[User talk:Tibfulv|talk]]) 17:49, 10 May 2016 (UTC) |
:: If you allow recursive regexes, it *is* possible to match EBNF with a regex: http://forums.xkcd.com/viewtopic.php?f=7&t=115494&p=3974658#p3974278 [[Special:Contributions/162.158.68.5|162.158.68.5]] 19:38, 10 May 2016 (UTC) | :: If you allow recursive regexes, it *is* possible to match EBNF with a regex: http://forums.xkcd.com/viewtopic.php?f=7&t=115494&p=3974658#p3974278 [[Special:Contributions/162.158.68.5|162.158.68.5]] 19:38, 10 May 2016 (UTC) |