Hi,
I know it is recommended to use eq to do string comparison,
but is == cause undefined behaviour? I tried this 
 
$a = "mssql";
if ($a == "mssql") {print "equal\n";} # gets print out as equal
$a = "MSSQL";
if ($a == "mssql") {print "equal\n";} # print equal
if ($a eq "mssql") {print "equal\n";} # print nothing

[download]
so it seems to be it is a case sensitive side effect but the
comparison still goes on. But my coworker says the behaviour
is undefined. Can anyone tell? Thanks

In reply to is behaviour undefined for string comparision with == by edwardt_tril

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