[GENERAL] "and then" / "or else"

Hi list,
the logical operators "and" and "or" are commutative, i.e. there is no "short-circuiting". Especially when doing PL/pgSQL development it would sometimes be very handy to have this short circuiting. Unfortunately, the trick from the docs (chapter 4.2.12) using "case ... then" does not work inside an "if" statement (the "then" of the "case" is interpreted as belonging to the "if" and thus leads to a syntax error). Of course, I can sometimes use nested "if" statements, but that doesn't always meet the logical requirements and leads to less readable code. Some programming languages (e.g. Eiffel) know the operators "and then" and "or else" which explicitly are "short-circuited". Would it be possible to add these operators to PostgreSQL in general or at least to the PL/pgSQL syntax?

Regards,

    Christian

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