33 lines
732 B
V
33 lines
732 B
V
// Function signatures can be declared as types:
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type Filter = fn (string) string
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// Functions can accept function types as arguments:
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fn filter(s string, f Filter) string {
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return f(s)
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}
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// Declare a function with a matching signature:
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fn uppercase(s string) string {
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return s.to_upper()
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}
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fn main() {
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// A function can be assigned to a matching type:
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my_filter := Filter(uppercase)
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// You don't strictly need the `Filter` cast - it's only used
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// here to illustrate how these types are compatible.
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// All of the following prints "HELLO WORLD":
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println(filter('Hello world', my_filter))
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println(filter('Hello world', uppercase))
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println(filter('Hello world', fn (s string) string {
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return s.to_upper()
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}))
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}
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