A web based playground for https://github.com/BenHanson/parsertl14 and https://github.com/BenHanson/lexertl14 based on https://github.com/BenHanson/gram_grep .

The playground website is based on https://yhirose.github.io/cpp-peglib/ and also with modifications based on https://chrishixon.github.io/chpeg/playground/ .

The playground save the grammar and the input in the local storage when you click Parse.

The playground has the following main elements:

• A select labeled Examples to choose one available example to start with.
• A select labeled Generate to optionally export Yacc/EBNF (for railroad diagrams).
• A button labeled Parse to build/execute the parser/grammar in the top left side editor over the input in the top right side editor.
• A bottom right side area to display info about the grammar (errors are clickable links to jump to line in the editor).
• A bottom left side area to display info about the input source parsing results (errors are clickabel to jump to line in the editor).
• A center left side foldable read only editor to show debug info about lexing/parsing the grammar or the input.

The availabel debugging options are:

• Input parse tree pruned
• Input parse tree full
• Input lexer dump
• Input parse trace
• Grammar parse tree pruned
• Grammar parse tree full
• Grammar lexer dump
• Grammar parse trace
• Grammar lexer state machine
• Grammar parse state machine

This project can also be built as a command line tool (see build.sh) then you can use it to check grammar/input on your disc:

./parsertl-playground
usage: ./parsertl-playground [options] grammar_fname input_fname
options can be:
-dumpil        Dump input lexer
-dumpiptree    Dump input parser tree
-dumpiptrace   Dump input parser trace
-dumpgl        Dump grammar lexer
-dumpgptree    Dump grammar parser tree
-dumpgptrace   Dump grammar parser trace
-dumpglsm      Dump grammar lexer state machine
-dumpgsm       Dump grammar parser state machine
-dumpAsEbnfRR  Dump grammar as EBNF for railroad diagram
-dumpAsYacc    Dump grammar as Yacc
-pruneptree    Do not show empty parser tree nodes
-verbose       Show several metrics for debug

The grammar used internally to parse the user grammar is this one playground-master.g the grammar has 4 sections:

/*Grammar header*/
%%
/*Grammar rules*/
%%
/*Lex header*/
%%
/*Lex rules*/
%%

The first two sections are equivalent to yacc/bison format and the other two sections are equivalent to lex/flex format.

Related projects:

• ANTLR Lab http://lab.antlr.org/
• Lezer playground https://lezer-playground.vercel.app/
• Tree-sitter https://tree-sitter.github.io/tree-sitter/playground
• Lpegrex/Lua https://mingodad.github.io/lua-wasm-playground/
• CocoR https://mingodad.github.io/CocoR-Typescript/playground
• CHPEG https://chrishixon.github.io/chpeg/playground/
• Cpp-Peglib https://yhirose.github.io/cpp-peglib/
• Jison https://gerhobbelt.github.io/jison/try/
• PeggyJS https://peggyjs.org/online.html
• Lark https://www.lark-parser.org/ide/
• Pest https://pest.rs/
• Ohm https://ohmjs.org/editor/
• Owl https://ianh.github.io/owl/try/#example
• Nearley Parser https://omrelli.ug/nearley-playground/
• Lalrpop http://lalrpop.github.io/lalrpop/
• Lezer https://lezer.codemirror.net/
• Syntax https://github.com/DmitrySoshnikov/syntax
• Antlr https://github.com/antlr/antlr4
• Textmapper https://textmapper.org/
• Railroad generator https://bottlecaps.de/rr/ui
• Convert (grammar conversion) https://www.bottlecaps.de/convert/
• Rex parser generator https://www.bottlecaps.de/rex/
• LALR https://github.com/cwbaker/lalr
• Ebnf Studio https://github.com/rochus-keller/EbnfStudio
• Bnf playground https://bnfplayground.pauliankline.com/
• Flexcpp https://gitlab.com/fbb-git/flexcpp
• Reflex https://www.genivia.com/doc/reflex/html/
• Bison https://www.gnu.org/software/bison/
• Flex https://github.com/westes/flex
• Byacc https://www.invisible-island.net/byacc/byacc.html
• BNF playground https://bnfplayground.pauliankline.com/
• Lrstar an LR(*) parser generator for C++ http://lrstar.cc/
• LangCC "A Next-Generation Compiler Compiler" https://github.com/jzimmerman/langcc