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.. Copyright (c) 2017-2026 Juancarlo Añez (apalala@gmail.com)
.. SPDX-License-Identifier: BSD-4-Clause
.. tatsu documentation master file, created by
sphinx-quickstart on Mon May 1 18:01:31 2017.
You can adapt this file completely to your liking, but it should at least
contain the root `toctree` directive.
.. include:: links.rst
|TatSu|
=======
*At least for the people who send me mail about a new language that
they're designing, the general advice is: do it to learn about how
to write a compiler. Don't have any expectations that anyone will
use it, unless you hook up with some sort of organization in a
position to push it hard. It's a lottery, and some can buy a lot of
the tickets. There are plenty of beautiful languages (more beautiful
than C) that didn't catch on. But someone does win the lottery, and
doing a language at least teaches you something.*
`Dennis Ritchie`_ (1941-2011) Creator of the C_ programming
language and of Unix_
|TatSu| is a tool that takes grammars in extended `EBNF`_ as input, and
outputs `memoizing`_ (`Packrat`_) `PEG`_ parsers in `Python`_. The classic
variations of EBNF_ (Tomassetti, EasyExtend, Wirth) and `ISO EBNF`_ are also
supported as input grammar format.
Why use a PEG_ parser? Because `regular languages`_ (those that can be parsed
with Python's ``re`` package) *"cannot count"*. Any language with nested structures
or with balancing of demarcations requires more than regular expressions to
be parsed.
|TatSu| can compile a grammar stored in a string into a ``tatsu.grammars``
object model. The model can be used to parse any input, much like the `re`_
module does with compiled regular expressions. The model can also be used to
generate a Python_ module that implements the parser.
|TatSu| supports `left-recursive`_ rules in PEG_ grammars, and it honors *left-associativity* in the resulting parse trees.
.. toctree::
:maxdepth: 4
intro
rationale
install
use
parserconfig
syntax
directives
ast
semantics
models
translation
left_recursion
mini-tutorial
traces
antlr
examples
support
credits
contributors
contributing
license
.. toctree::
:hidden:
.. comment out
Indices and tables
==================
* :ref:`genindex`
* :ref:`modindex`
* :ref:`search`
|
