string length 'hello, world' 12

set str foo

string length -q $str; echo $status 0

Equivalent to test -n "$str"

string length --visible (set_color red)foobar

the set_color is discounted, so this is the width of "foobar"

6

string length --visible 🐟🐟🐟🐟

depending on $fish_emoji_width, this is either 4 or 8

in new terminals it should be

8

string length --visible abcdef\r123

this displays as "123def", so the width is 6

6

string length --visible a\nbc

counts "a" and "bc" as separate lines, so it prints width for each

1 2

不接收参数不会输出（不是输出 0）