1.1 KiB
1.1 KiB
Side-Effect Considerations for Full Optimization Level
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All of Rhai's built-in functions (and operators which are implemented as functions) are pure
(i.e. they do not mutate state nor cause any side-effects, with the exception of print and debug
which are handled specially) so using [OptimizationLevel::Full] is usually quite safe unless
custom types and functions are registered.
If custom functions are registered, they may be called (or maybe not, if the calls happen to lie within a pruned code block).
If custom functions are registered to overload [built-in operators], they will also be called when
the operators are used (in an [if] statement, for example), potentially causing side-effects.
* _Always_ register custom types and functions _after_ compiling scripts if [`OptimizationLevel::Full`] is used.
* _DO NOT_ depend on knowledge that the functions have no side-effects, because those functions can change later on and,
when that happens, existing scripts may break in subtle ways.