textx

library4.3.0pypypi✓ verified 86d ago

textX is a meta-language for building Domain-Specific Languages (DSLs) in Python, inspired by Xtext. It allows you to define a grammar using a simple, intuitive syntax and then generates a parser and an object model for your DSL. The current version is 4.3.0, and it has a steady release cadence, primarily focusing on maintenance and Python version compatibility.

serialization web-framework

pip install textx

github ↗package ↗homepage ↗changelog ↗

INSTALL

IMPORT

SIG · TEXTX

textx

serializationpythonv4.3.0

Install

1.7s avg

Import

162ms

Disk

17MB

Pass rate

10/ 10

Env Coverage10 / 10

glibc

3.9–3.13

musl

3.9–3.13

Install & Compatibility

Where this runs

tested against v4.3.0 · pip install

no network on importno background threads

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

py 3.10–3.910 runs

installs and imports cleanly · install 0.0s · import 0.169s · 18.9MB

glibc

py 3.10–3.910 runs

installs and imports cleanly · install 1.7s · import 0.154s · 19MB

17MB installed

● package 17MB

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

metamodel_from_file

✓ from textx import metamodel_from_file

metamodel_from_str

✓ from textx import metamodel_from_str

TextXError

✓ from textx.exceptions import TextXError

TextXSyntaxError

✓ from textx.exceptions import TextXSyntaxError

This quickstart demonstrates how to define a simple grammar as a string, create a metamodel from it, and then parse an input string to build a model. It also shows basic error handling for invalid input.

from textx import metamodel_from_str grammar = """ Model: 'Hello' name=ID; ID: /[_a-zA-Z][a-zA-Z0-9_]*/; """ # Create a metamodel from the grammar string metamodel = metamodel_from_str(grammar) # Parse a model from an input string input_str = "Hello World" model = metamodel.model_from_str(input_str) # Access the parsed model data print(f"Parsed name: {model.name}") # Example with an error try: metamodel.model_from_str("Hi World") except Exception as e: print(f"Error parsing 'Hi World': {e}")

textx --version

Debug

Known issues

breakingPython 3.6 and 3.7 support was removed in textX 4.0.0. The minimum supported Python version is now 3.8.

fix

Upgrade your Python environment to 3.8 or newer before upgrading textX to version 4.0.0 or later.

affects: >=4.0.0

breakingThe separator in object rule references changed from `|` to `:` in version 3.1.0 and became a breaking change in 4.0.0. If your grammars use the old `|` separator for object references, they will fail to parse.

fix

Update your grammar files to use `:` as the object rule reference separator (e.g., `rule_name:obj_ref` instead of `rule_name|obj_ref`).

affects: >=4.0.0

gotchaInternal usage of `click.echo` was replaced with the standard Python `logging` module in version 4.2.0. This change primarily affects internal workings and custom CLI integrations that might have relied on `click.echo` for output.

fix

If you have custom tooling or integrations that intercept `click.echo` output, you may need to update them to capture standard Python `logging` output instead.

affects: >=4.2.0

gotchaThe regex for the `INT` rule was fixed in version 4.0.0, removing a word boundary (`\b`). This might slightly alter parsing behavior for specific edge cases where integers are immediately followed by non-word characters without a space, potentially making previously valid inputs invalid if the grammar implicitly relied on the old behavior.

fix

Test your existing grammars and input files thoroughly after upgrading to 4.0.0+ if they use the built-in `INT` rule and have complex integer parsing scenarios. Adjust your grammar or input as needed.

affects: >=4.0.0

Errors

Common errors & fixes

textx.exceptions.TextXSyntaxError: Expected '...', got '...' at position ...

The input text provided to the parser does not conform to the defined grammar rules. This is the most common error when developing a DSL.

fix

Carefully review your input string against your grammar definition. Use the textX CLI with the `--debug` flag (`textx generate --debug my_grammar.tx my_input.txt`) or `textx_tools.debugger` to visualize the parsing process and pinpoint the exact location of the syntax error.

textx.exceptions.TextXError: Unknown object '...' at position ...

A reference in the parsed model points to an object that has not been defined or is not in scope according to the grammar rules that handle references.

fix

Ensure that all referenced objects are correctly defined and named within your grammar. Verify that the input text contains the definitions of all objects before they are referenced. Check for typos in object names or reference rules.

textx.exceptions.TextXError: Rule '...' not found!

Your grammar file contains a reference to a rule that is not defined anywhere in the grammar, or there is a typo in a rule name.

fix

Inspect your grammar file for any misspelled rule names or rules that are declared but never defined. All rules mentioned in other rules or as the starting rule of the metamodel must have a corresponding definition.

Upgrade

Version history

4.3.0latest on PyPI · released Nov 25, 2025

Audit

Dependencies

No dependency data recorded yet.

Agent activity

12 hits · last 30 days

node

OpenAI (training)

Resources

githubhttps://github.com/textX/textX ↗

packagehttps://pypi.org/project/textx/ ↗

homepagehttps://textx.github.io/textX/ ↗

changeloghttps://github.com/textX/textX/blob/master/CHANGELOG.md ↗