[Issue 2547] New: Array Ops should check length, at least when bounds checking is on

[d-bugmail at puremagic.com]

http://d.puremagic.com/issues/show_bug.cgi?id=2547

           Summary: Array Ops should check length, at least when bounds
                    checking is on
           Product: D
           Version: 2.022
          Platform: PC
        OS/Version: Windows
            Status: NEW
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: bugzilla at digitalmars.com
        ReportedBy: dsimcha at yahoo.com


import std.stdio;

void main() {
    double[] foo = [1.0,2,3,4,5].dup;
    double[] bar = [6.0,7,8,9,10].dup;

    double[] baz = new double[1];
    baz[] = foo[] + bar[];
    writeln(baz);  // Prints [7].

    double[] waldo = new double[10];  // Should be all Nans.
    waldo[] = foo[] + bar[];
    writeln(waldo);  // Prints [7 9 11 13 15 0 0 0 7 9].

    double[] stuff = new double[10];
    stuff[] = foo[] + waldo[];
    writeln(stuff);  // Prints [8 11 14 17 20 0 0 0 8 11].
}
The array ops should either automatically change the lengths of baz[] and
waldo[] to match foo[] and bar[] (both in release and debug mode), or throw a
RangeError when bounds checking is enabled.  

In the last example, adding two arrays of different lengths either should not
be allowed and should throw a RangeError when bounds checking is enabled, or
should have reasonably well-defined behavior instead of the seemingly arbitrary
behavior exhibited.


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