
Induction of regular languages - tosh
https://en.wikipedia.org/wiki/Induction_of_regular_languages
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marktangotango
I wrote a parser for IBM mainframe job control language (JCL) a decade ago. It
was an interesting and infuriating excercise. I had access to several hundred
jobs in a production batch system to validate agaisnt and the IBM online
manual. When I was done I was sure I knew the code of the original and exactly
how it was implemented, even having never seen it.

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jaytaylor
The wiki page links to "Language identification in the limit" [0], aka
"LIitL", which is quite a cool idea about "learning" regular languages.

I've thought about making an inductive inference based regexp generator which
attempts to generate an expression for a given a set of inputs, but never got
around to investigating it thoroughly. Understanding the formal limitations on
what languages can be covered with this technique is satisfying.

[0]
[https://en.m.wikipedia.org/wiki/Language_identification_in_t...](https://en.m.wikipedia.org/wiki/Language_identification_in_the_limit)

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vzaliva
Some time ago I've applied Evolutionary Algorithms to the same problem. I did
not have much time to develop it further but I think it is another viable
approach in addition to ones listed.

[http://www.crocodile.org/lord/RSS_XML_Schema_induction.pdf](http://www.crocodile.org/lord/RSS_XML_Schema_induction.pdf)

