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closure

A small unnamed function you can write inline and store in a variable.

A closure is an anonymous function value, written with its parameters between vertical bars, that can use variables from the scope where it is written.

Examples

  • let double = |x| x * 2; then double(21) returns 42; the compiler works out the type of x from how the closure is used.

See also

capture mode Fn traits function pointer
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