It could be interesting to know, if the reason why this hasn't been
implemented already, is technical one, or a design decision?
I think it's design one since nobody took care to design it :) I personally don't see much need for it, since PHP is not a compiled language, so there's little use for specific syntax of prescribing value types. Since PHP has no concept of variable type, it's not clear what return type hinting would give you that good documenting practices and a decent IDE won't.
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Stanislav Malyshev, Zend Software Architect
stas@zend.com http://www.zend.com/
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