Re: What happens at the end of the file for lex?

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From	Philipp Klaus Krause <pkk@spth.de>
Newsgroups	comp.compilers
Subject	Re: What happens at the end of the file for lex?
Date	Thu, 4 Jun 2020 19:16:09 +0200
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Further investigation shows that this was an intentional, but
undocumented change in flex in 2015 (flex 2.5.4 input() returns EOF at
the end of the file, flex 2.6.4 input() returns 0). However I still have
no idea why this change was made.

I guess the only portable way to handle the end of the file is to set a
flag in yywrap() and check it each time input() was called.

Philipp
[Returning EOF was a bug.  The lex input() always returned 0 at end of file. -John]

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What happens at the end of the file for lex? Philipp Klaus Krause <pkk@spth.de> - 2020-06-03 10:04 +0200
  Re: What happens at the end of the file for lex? Philipp Klaus Krause <pkk@spth.de> - 2020-06-04 19:16 +0200

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