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IDE support

RTL patterns usually live inside Python string literals, which editors treat as plain text by default. pyRegTab ships editor tooling that improves this:

  1. Syntax highlighting — a TextMate grammar for .rtl files and for RTL embedded in Python strings (VS Code, PyCharm, and any TextMate-compatible editor).
  2. Runtime validation — an invalid RTL string is reported at RtlCompiler.compile(...) call time, with the exact source position.

Syntax highlighting

The grammar lives in the repository under ide/: ide/vscode/ is simultaneously a VS Code extension and an IntelliJ/PyCharm TextMate bundle.

VS Code

Copy the extension into your extensions directory and reload:

# Linux / macOS
cp -r ide/vscode ~/.vscode/extensions/regtab.rtl-language-0.1.0

:: Windows
xcopy /E /I ide\vscode %USERPROFILE%\.vscode\extensions\regtab.rtl-language-0.1.0

(Or package a proper .vsix with npx @vscode/vsce package inside ide/vscode.)

This highlights *.rtl files and RTL inside Python strings in these forms:

pattern = RtlCompiler.compile("""
    [ [ATTR] [VAL : (LT{1})->REC]+ ]+
""")

single = RtlCompiler.compile("[ [ATTR] [VAL]+ ]")

Limitation

TextMate matching is line-based: the opening quote must be on the same line as RtlCompiler.compile(.

PyCharm / IntelliJ IDEA

Settings → Editor → TextMate Bundles → “+” and select the ide/vscode directory — *.rtl files are highlighted. For RTL inside Python string literals, PyCharm's built-in language injection recognizes the # language=RTL line-comment marker, where the IDE version supports injecting TextMate-backed languages.

Runtime validation

Python has no javac-style compile-time annotation processor (the jRegTab counterpart is the @RtlSource annotation validated during compilation). In pyRegTab, RTL is validated when the string is compiled: RtlCompiler.compile(...) raises RtlCompileError with the source position, expected tokens, and a fragment of the offending input.

from pyregtab import RtlCompiler, RtlCompileError

try:
    RtlCompiler.compile("[ [VAL ]")   # missing ']'
except RtlCompileError as e:
    print(e)   # RTL compile error at 1:8: expected ']', found Eof

Catch these early by compiling patterns once at import time (module-level constants) — an invalid pattern then fails on first import rather than deep inside a run.