34 lines
961 B
Markdown
34 lines
961 B
Markdown
Disable Looping
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===============
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{{#include ../links.md}}
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For certain scripts, especially those in embedded usage for straight calculations, or where Rhai
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script [`AST`]'s are eventually transcribed into some other instruction set, looping may be
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undesirable as it may not be supported by the application itself.
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Rhai looping constructs include the [`while`], [`loop`], [`do`] and [`for`] statements.
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Although it is possible to disable these keywords via
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[`Engine::disable_symbol`][disable keywords and operators], it is simpler to disable all looping
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via [`Engine::set_allow_looping`][options].
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```rust
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use rhai::Engine;
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let mut engine = Engine::new();
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// Disable looping
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engine.set_allow_looping(false);
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// The following all return parse errors.
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engine.compile("while x == y { x += 1; }")?;
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engine.compile(r#"loop { print("hello world!"); }"#)?;
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engine.compile("do { x += 1; } until x > 10;")?;
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engine.compile("for n in 0..10 { print(n); }")?;
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```
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