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_archive/rhai_engine/rhaibook/safety/max-functions.md

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+Maximum Number of Functions
+===========================
+
+{{#include ../links.md}}
+
+Rhai by default does not limit how many [functions] can be defined in a script.
+
+This can be changed via the [`Engine::set_max_functions`][options] method. Notice that setting the
+maximum number of [functions] to zero does _not_ indicate unlimited [functions], but disallows
+defining any scripted [function] altogether.
+
+A script attempting to load more than the maximum number of [functions] will terminate with a parse error.
+
+This check can be disabled via the [`unchecked`] feature for higher performance (but higher risks as well).
+
+```rust
+let mut engine = Engine::new();
+
+engine.set_max_functions(5);        // allow defining only up to 5 functions
+
+engine.set_max_functions(0);        // disallow defining function (maximum = zero)
+
+engine.set_max_functions(1000);     // set to a large number for effectively unlimited functions
+```