52 lines
1.2 KiB
Markdown
52 lines
1.2 KiB
Markdown
`if` Statement
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==============
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{{#include ../links.md}}
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`if` statements follow C syntax:
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```rust
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if foo(x) {
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print("It's true!");
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} else if bar == baz {
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print("It's true again!");
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} else if baz.is_foo() {
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print("Yet again true.");
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} else if foo(bar - baz) {
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print("True again... this is getting boring.");
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} else {
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print("It's finally false!");
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}
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```
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Braces Are Mandatory
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--------------------
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Unlike C, the condition expression does _not_ need to be enclosed in parentheses '`(`' .. '`)`', but
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all branches of the `if` statement must be enclosed within braces '`{`' .. '`}`',
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even when there is only one statement inside the branch.
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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!");
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// ^ syntax error, expecting '{' in statement block
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```
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`if`-Expressions
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---------------
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Like Rust, `if` statements can also be used as _expressions_, replacing the `? :` conditional operators
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in other C-like languages.
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```rust
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// The following is equivalent to C: int x = 1 + (decision ? 42 : 123) / 2;
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let x = 1 + if decision { 42 } else { 123 } / 2;
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x == 22;
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let x = if decision { 42 }; // no else branch defaults to '()'
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x == ();
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```
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