56 lines
1.3 KiB
Markdown
56 lines
1.3 KiB
Markdown
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`for` Loop
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==========
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{{#include ../links.md}}
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Iterating through a range or an [array] is provided by the `for` ... `in` loop.
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```rust
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// Iterate through string, yielding characters
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let s = "hello, world!";
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for ch in s {
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if ch > 'z' { continue; } // skip to the next iteration
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print(ch);
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if x == '@' { break; } // break out of for loop
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}
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// Iterate through array
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let array = [1, 3, 5, 7, 9, 42];
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for x in array {
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if x > 10 { continue; } // skip to the next iteration
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print(x);
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if x == 42 { break; } // break out of for loop
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}
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// The 'range' function allows iterating from first to last-1
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for x in range(0, 50) {
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if x > 10 { continue; } // skip to the next iteration
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print(x);
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if x == 42 { break; } // break out of for loop
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}
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// The 'range' function also takes a step
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for x in range(0, 50, 3) { // step by 3
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if x > 10 { continue; } // skip to the next iteration
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print(x);
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if x == 42 { break; } // break out of for loop
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}
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// Iterate through object map
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let map = #{a:1, b:3, c:5, d:7, e:9};
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// Property names are returned in random order
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for x in keys(map) {
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if x > 10 { continue; } // skip to the next iteration
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print(x);
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if x == 42 { break; } // break out of for loop
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}
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// Property values are returned in random order
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for val in values(map) {
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print(val);
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}
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```
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