82 lines
906 B
Markdown
82 lines
906 B
Markdown
# Lambdas / Anonymous functions
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## Anonymous function
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```thp
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fun(Int x, Int y) -> Int {
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x + y
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}
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numbers.map(fun(x) {
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x * 2
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})
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```
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## Closure types
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By default closures **always** capture variables as **references**.
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```thp
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var x = 20
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val f = fun() {
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print(x)
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}
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f() // 20
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x = 30
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f() // 30
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```
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You can force a closure to capture variables by value.
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```thp
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fun(parameters) clone(variables) {
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// code
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}
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```
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```thp
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var x = 20
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val f = fun() clone(x) {
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print(x)
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}
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f() // 20
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x = 30
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f() // 20
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```
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## Lambdas
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Lambdas are a short form of anonymous functions. They are declared with `#{}`.
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Inside the lambda you can access the parameters as `$1`, `$2`, etc.
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Finally, lambdas be written outside of the parenthesis of function calls.
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```thp
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numbers.map() #{
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$1 * 2
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}
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// the above lambda is equivalent to:
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numbers.map(fun(param1) {
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$1 * 2
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})
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```
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