Yes, what's really going on here is that, while the computer treats $a == $b as commutative, the human brain is linguistically wired, and tends to parse such constructs asymmetrically as a topic and a predicate. And as it happens, the topic likes to be first. For similar reasons most OO programmers will choose to write: 
    foo.equals(0)

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rather than: 
    0.equals(foo)

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Despite the fact that Ruby considers 0 to be a Real Object, I suspect that even Ruby programmers will prefer the first form to the second, because that's how our brains are wired.

The solution to all this in Perl 6 will be that assignment to an existing variable in boolean context will produce a warning under strictures, but assignment to a my declaration will not. The typical use for assignment in a boolean context is actually not the if statement but the while statement: 

    while $item = shift(@foo) {...}

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and in most cases this is probably better written as: 
    while my $item = shift(@foo) {...}

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or even better: 
    for @foo -> $item {...}

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Likewise, 
    if $x = long_expression() {...}

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can turn into 
    given long_expression -> $x {...}

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I suppose we might also allow the gcc-like workaround of putting extra parens when you want to hide the assignment from the boolean context.

In reply to Re^2: Avoiding the == blues by TimToady
in thread Avoiding the == blues by friedo

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