ANTLR, Dynamic variables

Posted by JTS on Stack Overflow See other posts from Stack Overflow or by JTS
Published on 2010-06-11T16:28:11Z Indexed on 2010/06/11 16:32 UTC
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antlr

Hello,

I have an ANTLR grammar that can parse and evaluate simple expressions like 1+2*4, etc. What I would like to do is to evaluate expressions like 2+$a-$b/4 where the $ variables are dynamic variables, that come from an external source and are continuously updated.

Is there any design pattern on how to do this using ANTLR, best practices, etc?

Shall I "substring" the $a with the updated value ($a -> 4.34)
A nicer way to do this?

Thx

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ANTLR, Dynamic variables

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