41 lines
736 B
Go
41 lines
736 B
Go
package go_koans
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func aboutPointers() {
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{
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a := 3
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b := a // 'b' is a copy of 'a' (all assignments are copy-operations)
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b++
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assert(a == 3) // variables are independent of one another
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}
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{
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a := 3
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b := &a // 'b' is the address of 'a'
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*b = *b + 2 // de-referencing 'b' means acting like a mutable copy of 'a'
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assert(a == 5) // pointers seem complicated at first but are actually simple
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}
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{
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increment := func(i int) {
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i++
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}
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a := 3
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increment(a)
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assert(a == 3) // variables are always passed by value, and so a copy is made
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}
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{
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realIncrement := func(i *int) {
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(*i)++
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}
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b := 3
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realIncrement(&b)
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assert(b == 4) // but passing a pointer allows others to mutate the value pointed to
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}
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}
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