forked from steger/pr3-sose2026
32 lines
1.0 KiB
Go
32 lines
1.0 KiB
Go
package main
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import (
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"fmt"
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"runtime"
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)
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func main() {
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//create an array with a lot of data
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massiveData := make([]int, 1_000_000)
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for i := range massiveData {
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massiveData[i] = i
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}
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// Task: Extract the first 8 elements safely
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//1. attempt: use the slice operator
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//smallSlice := massiveData[:8]
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// consequence -> smallSlice and massiveData point to the same underlying array.
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// Therefore, setting massiveData to nil is not sufficient to release that big array.
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//2. attempt: create a new slice (with a new underlying array) and copy data
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smallSlice := make([]int, 8)
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copy(smallSlice, massiveData[:8])
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massiveData = nil //don't use massive data anymore: Underlying array shall be freed.
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runtime.GC() //run the garbage collector to make sure that all unused data is actually freed
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//cap(smallSlice) should be 8 or similar, but not close to 1_000_000. The majority of the data should have been released by now
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fmt.Printf("Small Slice: %v, Len: %d, Cap: %d\n", smallSlice, len(smallSlice), cap(smallSlice))
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}
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