bytedeco/javacpp

Add support variadic templates

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#81 opened on Feb 28, 2016

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enhancementhelp wanted

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Description

Add support for variadic templates

eg.

template <typename... Arguments> returntype functionname(Arguments... args);

or

template<typename ...Arguments> class classname;

Currently this throws an NPE:

Caused by: java.lang.NullPointerException
    at org.bytedeco.javacpp.tools.Parser.parameters(Parser.java:1366)
    at org.bytedeco.javacpp.tools.Parser.declarator(Parser.java:845)
    at org.bytedeco.javacpp.tools.Parser.function(Parser.java:1457)
    at org.bytedeco.javacpp.tools.Parser.declarations(Parser.java:2639)
    at org.bytedeco.javacpp.tools.Parser.group(Parser.java:2214)
    at org.bytedeco.javacpp.tools.Parser.declarations(Parser.java:2638)
    at org.bytedeco.javacpp.tools.Parser.namespace(Parser.java:2544)
    at org.bytedeco.javacpp.tools.Parser.declarations(Parser.java:2637)
    at org.bytedeco.javacpp.tools.Parser.parse(Parser.java:2713)
    at org.bytedeco.javacpp.tools.Parser.parse(Parser.java:2806)
    at org.bytedeco.javacpp.tools.Builder.parse(Builder.java:69)
    at org.bytedeco.javacpp.tools.Builder.build(Builder.java:625)
    at org.bytedeco.javacpp.tools.BuildMojo.execute(BuildMojo.java:226)```

Contributor guide

Research direction
Investigate the NullPointerException at Parser.java:1366 (parameters method). Study how template parameter lists are currently parsed and add support for the variadic '...' syntax in both function and class templates. Trace the parsing flow from the stack trace to understand the expected structure.
Tech stack
javacpp
Domain
compilersbackend
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
Half day
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
JavaC++ template syntax
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
60