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Interpreter fails Type::Library extends during BEGIN

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已經有一個關聯 PR 被合併了。

  • #1751 來自 @fglock —— 已合併

評估

難度
4/5
預估耗時
3-5 天
新手友好度
58/100
Issue 類型
缺陷
描述清晰度
描述清楚
活躍度
活躍
技術堆疊
java, perl
領域
backend, compilers

研究方向

Start with the minimal probe and run it using ./jperl --interpreter probe.pl, then compare its behavior with system Perl and JVM PerlOnJava. Trace interpreter handling of the package @ISA changes made by Type::Library -base before Type::Utils::extends performs its caller isa('Type::Library') check. Done means the probe and Dancer2's Dancer2/Core/Types.pm initialize without the Not a type library error on the interpreter backend.

由索引模型根據 Issue 內容生成。

描述

area:runtime bug

Summary

Dancer2 cannot load on the interpreter backend because its Dancer2::Core::Types type library fails during BEGIN { extends "Types::Standard" } with Not a type library.

Reproduction

package Probe::Types;
use strict;
use warnings;
use Type::Library -base;
use Type::Utils -all;
BEGIN { extends 'Types::Standard' }
print "loaded\n";

Run with ./jperl --interpreter probe.pl. The JVM backend and system Perl load this successfully; the interpreter reports Not a type library at the extends call. Dancer2's Dancer2/Core/Types.pm uses this same pattern and fails at its corresponding line 10.

Root cause

Type::Utils::extends checks that its caller isa('Type::Library'). Type::Library -base installs Type::Library in the caller package's @ISA during module setup. The interpreter does not expose that inheritance to the subsequent isa check in the same BEGIN block, although the JVM backend does. This prevents Dancer2's type library from initializing, so Dancer2 is not currently usable on the interpreter backend.

Evidence

  • use Type::Library -base alone succeeds under the interpreter.
  • The minimal extends 'Types::Standard' reproducer fails only under the interpreter.
  • The equivalent probe succeeds under JVM PerlOnJava and system Perl.
主要語言
Perl
星號
64
分支
8
平均合併
5 小時 52 分鐘
30 天內合併 PR
194

環境準備

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  • 沒有 Pull Request 範本
  • 閱讀貢獻指南

從這裡開始

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  3. Fork 儲存庫，在一個分支上完成修改。
  4. 送出 Pull Request，並在描述裡引用這個 Issue 編號。

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