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User-specification of syntax highlighting (e.g. for specialized modeling languages, like GAMS)
n++, VIM, etc. allow user- based extension to new syntaxes.
I would like to add the reserved words, comment delimiters, etc. for GAMS, a specialized modeling language. Others may have their own customization needs.
Customer support service by UserEcho
I'm currently working on Textastic 3.0 which is going to support custom syntax definitions using TextMate bundles.