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digitalmars.D.learn - Easy bug: reference to local variable

Nothing new here but I almost fell prey to this bug today. Spot the bug:

import std.stdio;
import std.range;

int[3] bar() {
     return [ 1, 2, 3 ];
}

auto foo() {
     auto a = bar();
     return zip(a[], a[]);
}

void main() {
     writeln(foo());
}

In the real code, bar() was a call to std.datetime.benchmark, which also 
returns a static array. (The compiler is helpful in the trivial case of 
foo returning a[] instead of hiding it through zip.)

DIP 1000 is targeting such bugs:

   https://github.com/dlang/DIPs/blob/master/DIPs/DIP1000.md

Ali
Sep 01 2017