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Stream parser/make_lexer
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Date: 2005-06-26 (10:12)
From: Sen Horak <sen.horak@g...>
Subject: Stream parser/make_lexer
Hi,

I tried building a small parser using Genlexer.make_parser and the
stream parser through the camlp4 preprocessor. I'm using the ocaml
compiler 3.08.1.

let lexer=make_lexer ["begin";"end";...]

let parse = parser
      [<'Kwd "name=";'String t>] -> wm#setname t
  |  ...

let istream = of_channel stdin

let ilexer = lexer istream in
  parse ilexer

The program exits with a Stream.Failure exception. The "stream
builders" documentation clearly says that we are not to mix the of_*
functions to build streams with <> streams - so I guess this is
expected. Although I've come across some examples that use of_string
to build the char stream and use the lexer on it.

How then does one build a stream compatible with the stream parser
connected to stdin?

Also, is the make_lexer/stream parser way of building a parser
deprecated? I find it a convenient way to build small parsers quickly.
Or do most ocaml programmers just use ocamllex/ocamlyacc for
everything?

SH