rhai/doc/src/language/if.md

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`if` Statement
==============
{{#include ../links.md}}
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`if` statements follow C syntax:
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```rust
if foo(x) {
print("It's true!");
} else if bar == baz {
print("It's true again!");
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} else if baz.is_foo() {
print("Yet again true.");
} else if foo(bar - baz) {
print("True again... this is getting boring.");
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} else {
print("It's finally false!");
}
```
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Unlike C, the condition expression does _not_ need to be enclosed in parentheses '`(`' .. '`)`', but
all branches of the `if` statement must be enclosed within braces '`{`' .. '`}`',
even when there is only one statement inside the branch.
Like Rust, there is no ambiguity regarding which `if` clause a branch belongs to.
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```rust
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// Rhai is not C!
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if (decision) print("I've decided!");
// ^ syntax error, expecting '{' in statement block
```
`if`-Expressions
---------------
Like Rust, `if` statements can also be used as _expressions_, replacing the `? :` conditional operators
in other C-like languages.
```rust
// The following is equivalent to C: int x = 1 + (decision ? 42 : 123) / 2;
let x = 1 + if decision { 42 } else { 123 } / 2;
x == 22;
let x = if decision { 42 }; // no else branch defaults to '()'
x == ();
```