31 lines
1016 B
Markdown
31 lines
1016 B
Markdown
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Function Pointer Currying
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========================
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{{#include ../links.md}}
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It is possible to _curry_ a [function pointer] by providing partial (or all) arguments.
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Currying is done via the `curry` keyword and produces a new [function pointer] which carries
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the curried arguments.
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When the curried [function pointer] is called, the curried arguments are inserted starting from the left.
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The actual call arguments should be reduced by the number of curried arguments.
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```rust
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fn mul(x, y) { // function with two parameters
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x * y
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}
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let func = Fn("mul");
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func.call(21, 2) == 42; // two arguments are required for 'mul'
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let curried = func.curry(21); // currying produces a new function pointer which
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// carries 21 as the first argument
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let curried = curry(func, 21); // function-call style also works
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curried.call(2) == 42; // <- de-sugars to 'func.call(21, 2)'
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// only one argument is now required
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```
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