Hello,
can somebody comment on the Remark from
https://www.freepascal.org/docs-html/ref/refch12.html ?
/Remark: The order in which expressions of the same precedence are
evaluated is not guaranteed to be left-to-right./
Is this valid for boolean expressions, too? I use the following
construct with {$BOOLEVAL OFF}:
Result := Assigned(MyObject) and (MyObject.Value>5);
The remark above suggests that I cannot use it because
(MyObject.Value>5) may be evaluated before Assigned(MyObject) if the
optimizer decides so.
On the other hand, the information in
https://www.freepascal.org/docs-html/current/prog/progsu4.html#x11-100001.2.4
suggests the opposite:
/So, in the following example, the function Bofu, which has a boolean
result, will never get called.//
//If False and Bofu then/
Delphi documentation also explicitly states that the expressions are
evaluated in left to right order:
http://docwiki.embarcadero.com/RADStudio/Rio/en/Boolean_short-circuit_evaluation_(Delphi_compiler_directive)
(Well it is no surprise because
https://www.freepascal.org/docs-html/ref/refch12.html states that "/This
behaviour is distinctly different from Delphi or Turbo Pascal./")
Ondrej
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