基本使用¶
- byte_size/1
// Bitstring有多少个bytes,不够8位的也按1个算
byte_size(Bitstring) -> integer() >= 0
> byte_size(<<433:16,3:3>>).
3
> byte_size(<<1,2,3>>).
3
- element/2
// 返回第N个元素值,N从1开始
element(N, Tuple) -> term()
- iolist_to_binary/1
// 把iolist() | binary()数据转为binary()
iolist_to_binary(IoListOrBinary) -> binary()
> Bin1 = <<1,2,3>>.
<<1,2,3>>
> Bin2 = <<4,5>>.
<<4,5>>
> Bin3 = <<6>>.
<<6>>
> iolist_to_binary([Bin1,1,[2,3,Bin2],4|Bin3]).
<<1,2,3,1,2,3,4,5,4,6>>
- trunc/1
trunc(Number) -> integer()
类型:
Number = number()
实例:
erl> trunc(5.5).
5
- tuple_size/1
// 返回Tuple的个数
tuple_size(Tuple) -> integer() >= 0
tuple_size({morni, mulle, bwange}). // 3
- pid_to_list/1
pid_to_list(Pid).
- list_to_pid/1
list_to_pid("<0.0.0>").
% pid(0,0,0). 只适用于shell