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zycbobby/data-constructor.go

Last active November 3, 2015 03:51
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data-constructor.go
func NewFile(fd int, name string) *File {
if fd < 0 {
return nil
}
f := File{fd, name, nil, 0}
return &f
}
Raw
data-make.go
# The reason for the distinction is that these three types represent, under the covers, references to data structures that must be initialized before use.
var p *[]int = new([]int) // allocates slice structure; *p == nil; rarely useful
var v []int = make([]int, 100) // the slice v now refers to a new array of 100 ints
// Unnecessarily complex:
var p *[]int = new([]int)
*p = make([]int, 100, 100)
// Idiomatic:
v := make([]int, 100)
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zycbobby commented Nov 3, 2015

make slice

  • Remember that make applies only to maps, slices and channels and does not return a pointer. To obtain an explicit pointer allocate with new or take the address of a variable explicitly.

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