Change BNF arrow notation from -> to =>

[Copilot]

The BNF language used -> for rule arrows, which should be => to match standard BNF notation conventions.

Changes

Grammar

• bnf/Dsp.g4: Updated rule syntax from '->' to '=>'

Implementation

• bnf/apyds_bnf/__init__.py: Modified UnparseVisitor to generate =>
• bnf/atsds_bnf/index.mjs: Modified UnparseVisitor to generate =>

Documentation

• bnf/README.md: Updated all syntax examples
• docs/support-packages/bnf.md: Updated all syntax examples

Tests

• bnf/tests/test_parse_unparse.py: Updated test expectations
• bnf/tests/test_parse_unparse.mjs: Updated test expectations

Example

Before:

premise1, premise2 -> conclusion

After:

premise1, premise2 => conclusion

The parsers will regenerate automatically during the build process.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• central.sonatype.com
  • Triggering command: /home/REDACTED/.local/bin/antlr4 antlr4 --version (dns block)
• www.antlr.org
  • Triggering command: /usr/bin/wget wget -q REDACTED (dns block)
  • Triggering command: /usr/bin/curl curl -o antlr-4.13.2-complete.jar REDACTED (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Original prompt

---

This section details on the original issue you should resolve

<issue_title>bnf 语言部分， "->" 应该是 "=>"</issue_title>
<issue_description>多个地方需要修改

1. bnf/*.g4
2. bnf/apyds_bnf/*
3. bnf/atsds_bnf/*
4. bnf/README.md
5. docs/support-packages/*</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes bnf 语言部分， "->" 应该是 "=>" #121

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[Copilot]

Pull request overview

This PR updates the BNF language arrow notation from -> to => to align with standard BNF notation conventions. The change is consistently applied across the grammar definition, implementation code, documentation, and tests.

Key Changes:

• Updated grammar rule syntax to use '=>' instead of '->'
• Modified unparse visitors in both Python and JavaScript implementations to generate =>
• Updated all documentation examples and test cases to reflect the new syntax

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
bnf/Dsp.g4	Updated grammar rule definition to use '=>' for rule arrows
bnf/apyds_bnf/init.py	Modified UnparseVisitor.visitRule to generate => in output
bnf/atsds_bnf/index.mjs	Modified UnparseVisitor.visitRule to generate => in output
bnf/README.md	Updated all syntax examples in documentation to use =>
docs/support-packages/bnf.md	Updated all syntax examples in documentation to use =>
bnf/tests/test_parse_unparse.py	Updated all test cases including error scenarios to use new syntax
bnf/tests/test_parse_unparse.mjs	Updated all test cases including error scenarios to use new syntax

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