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Parsing a postfix expression in C#, my naive approach

, 19 Dec 2010
Regex combined = new Regex(@"\G(\s+(?[+-*/])|\s*(?-?[0-9]+))", RegexOptions.ExplicitCapture);This line has an error:parsing "\G(\s+(?[+-*/])|\s*(?-?[0-9]+))" - [x-y] range in reverse order.

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22 Nov 2010
CPallini
3 alternatives  
There was a request about in Q&A. The question was deleted, anyway I think the subject may be interesting.
21 Dec 2010
Morten Nilsen
Here is my take on the same, using Lambda expressions and slightly more advanced regular expression features:I have not tested this code, so errors may exist.This implementation will ignore unrecognized tokens. namespace Postfix { class Parser { static Dictionary<string,...
21 Dec 2010
Andreas Gieriet
For those who like dense code, here is a sample :) - Make the dictionary static readonly, init directly- Swap the arguments in the lambda expressions and call by direct pop from the stack- Make the regex simpler and put the logic of parsing into the Exec (the regex only tokenizes the...

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YangChunJiang

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