new warning: operator negate should return a numeric type on vector and matrix types

[DartBot]

This issue was originally filed by joh...@johnmccutchan.com

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Upgrading to the latest version of DartEditor I noticed a new warning for the following code:

  /// Returns a new vec2 from -this
  vec2 operator negate() => new vec2(-x, -y);

The warning is: operator negate should return a numeric type.

Vectors and matrices are numeric types and I expect to be able to use negate on them. Can this be relaxed?

Thanks,
John

[sethladd]

Redirecting to Analyzer first to verify correct behavior.

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Added Area-Analyzer, Triaged labels.

[bwilkerson]

Version 0.10 of the spec states

  It is a static warning if the return type of the user-declared operator
  negate is explicitly declared and not a numerical type.

This requirement will probably be removed in version 0.11 (as indicated by http://code.google.com/p/dart/issues/detail?id=3765), and if so editor will then relax the restriction, but we are currently waiting to see whether that change is actually approved. You can follow the editor's progress using this issue: http://code.google.com/p/dart/issues/detail?id=3768.

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Added Duplicate label.
Marked as being merged into #3768.