Go語(yǔ)言中有自動(dòng)垃圾回收的機(jī)制(garbage collection)，不需要為內(nèi)存回收擔(dān)心。而內(nèi)存分配的有兩種操作方式，new和make，本節(jié)重點(diǎn)講述這兩種操作方式。
new
內(nèi)置函數(shù)new與其他語(yǔ)言類似，new(T)為T(mén)類型分配一個(gè)零空間，并返回其地址，即*T類型的值。或者換句話說(shuō)，它返回一個(gè)指向新分配的T類型零值的指針，這一點(diǎn)需要牢記。
bytes.Buffer 的文檔指出“Buffer 的零值是一個(gè)可以使用的空緩沖區(qū)”。 同樣，sync.Mutex沒(méi)有顯式構(gòu)造函數(shù)或Init方法。 相反，sync.Mutex 的零值被定義為未鎖定的互斥鎖。
參數(shù)定義
func new(Type) *Type
The new built-in function allocates memory. The first argument is a type, not a value, and the value returned is a pointer to a newly allocated zero value of that type.
make
內(nèi)置的make(T)僅用于創(chuàng)建slices, maps和channels，返回類型T的初始化值(非零!)，并且不是一個(gè)指針*T。產(chǎn)生這種區(qū)別的原因，是在使用前引用的數(shù)據(jù)類型必須進(jìn)行初始化。
參數(shù)定義
func make(t Type, size ...IntegerType) Type
The make built-in function allocates and initializes an object of type slice, map, or chan (only). Like new, the first argument is a type, not a value. Unlike new, make's return type is the same as the type of its argument, not a pointer to it. The specification of the result depends on the type:
Slice: The size specifies the length. The capacity of the slice is equal to its length. A second integer argument may be provided to specify a different capacity; it must be no smaller than the length. For example, make([]int, 0, 10) allocates an underlying array of size 10 and returns a slice of length 0 and capacity 10 that is backed by this underlying array. Map: An empty map is allocated with enough space to hold the specified number of elements. The size may be omitted, in which case a small starting size is allocated. Channel: The channel's buffer is initialized with the specified buffer capacity. If zero, or the size is omitted, the channel is unbuffered.
區(qū)別
new只負(fù)責(zé)分配，make負(fù)責(zé)初始化，區(qū)別點(diǎn)：
- new(T)返回指針，*T指向零值T
- make(T)返回初始化后的T
