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Berp

A flexible cross-language parser generator with support for languages without explicit tokenization rules (like Gherkin).

It can be installed from NuGet. The executable is within the tools/net471 folder inside the package.

generates parser for it's own grammar (the "hello world" for parser generators), see Berp Grammar
does not generate a lexer/tokenizer, so ideal for languages where tokenization is easy or anyway not really possible
simple, BNF-like grammar definition
supports multiple target languages (currently C#, Java, Ruby, JavaScript, Go, Python) with the same grammar (the language generation is specified in template files)
allows building AST, with AST-building hooks
supports streamed token reading (tokens can be kept attached to the input stream to avoid unnecessary data transfer and object creation)
supports context-sensitive tokens, also possible to change the tokenization rules during parsing (e.g. when a #language: no is encountered)
supports a special "other" token, that matches to the "anything-else" case, when there is no better match
support for recursive grammar rules is limited (it parses them up to a certain level only)
simple, look-ahead rules can be specified
rules can be marked as production rules to be represented in AST
allows capturing ignored content tokens (e.g. comments)