Consider the following program:

struct S1 {
    enum member = 3;
}

struct S2 {
    enum member = 2;
}

struct S3 {
}

enum prop(T) = __traits(hasMember, T, "member") && T.member==3;

pragma(msg, prop!S1);
pragma(msg, prop!S2);
pragma(msg, prop!S3);

When compiled, it produces:
true
false
test.d(12): Error: no property member for type S3
test.d(16): Error: template instance `test.prop!(S3)` error instantiating
test.d(16):        while evaluating pragma(msg, prop!(S3))

If I change the definition of "prop" to:
template prop(T) {
    static if( __traits(hasMember, T, "member") && T.member==3 )
        enum prop = true;
    else
        enum prop = false;
}

then everything compiles as expected.

It seems that the && evaluation does not stop when the first false is found.

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