[nem-bug] [Nemerle 0001026]: user-defined operators break type-inference

[feedback at nemerle.org]

A NOTE has been added to this issue.
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<http://nemerle.org/bugs/view.php?id=1026> 
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Reported By:                divan
Assigned To:                
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Project:                    Nemerle
Issue ID:                   1026
Category:                   Compiler (type engine)
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     new
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Date Submitted:             06-12-2007 16:53 CEST
Last Modified:              06-13-2007 18:00 CEST
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Summary:                    user-defined operators break type-inference
Description: 
using System;
using DateHelper;

public module DateHelper {
  public @+ (date : DateTime, delta : double) : DateTime {
    date.AddDays (delta);
  }
  public @+ (_ : int, _ : DateTime) : int {
    1
  }
}

_ = [1.0].FoldLeft (2.0, _ + _)

Results in error, but should choose double+double overload.
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----------------------------------------------------------------------
 divan - 06-13-07 18:00 
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1)One more example:
_ = (_ + _) ([1], [2]);
or even
_ = (op_Addition : _ ->  _) ([1], [2]);
gets same errors but can be fixed by "using Nemerle.Core.list"

2)module DateHelper can be replaced with class A, and operators A+int,
int+A, same errors

3)It looks like it's the problem only with operators, because replacing @+
with for example "string", and testing _ = (string : _ -> _) ('a', 1);
works ok, choosing one of string constructors.

Issue History
Date Modified  Username       Field                    Change              
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06-12-07 16:53 divan          New Issue                                    
06-13-07 18:00 divan          Note Added: 0001916                          
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