Background
I want to be able to parse Javascript source in a Delphi Application. I need to be able to identify variables and functions within the source for the purpose of making changes to the code through later code. I understand that I probably need to use a lexer for this purpose but have not had much luck using the lexer which I found (Dyaclexx).
Question
Is there a suitable freeware or open source delphi parser/lexer which already has token sets for Javascript or could be easily modified for this purpose without too much trouble?
If there isn't such a tool already available then what would be the best way to learn about writing your own lexer for this purpose?
Thank-you
For the lexer you can see Synedit's source code for the Javascript highlighter. A highlighter in Synedit context is a lexer with special hooks to provide highlighting to the editor component. Trimming those hooks and getting a plain lexer is a trivial job.
Also Synedit editor can come handy while learning how to build lexers as it will be a help to visually test your lexers real-time. You can see the demos or ask at the mailing list for more.
I think you should use should look at GoldParser (http://www.devincook.com/goldparser) for generating a complete JS parser in Delphi code. GoldParser is freeware though.
来源：https://stackoverflow.com/questions/354563/what-would-be-a-good-delphi-lexer-parser-for-javascript-language-file