Empty string: Difference between revisions

=={{header|Z80 Assembly}}==

{{trans|6502 Assembly}}

An empty string is just a null terminator with no text in front.

<lang z80>EmptyString:

byte 0</lang>

Checking if a string is empty is simple, just count the number of characters before you reach the terminator. If that count equals zero, the string is empty. Otherwise, the string is not empty.

<lang z80>ld hl,MyString

GetStringLength:

ld b,0 ;zero the length counter

loop_getStringLength:

ld a,(hl)

or a ;compare A to zero

ret z ;exit if zero

inc hl ;next char

inc b ;add 1 to length counter

jr loop_getStringLength

ld b,a

or a

jr z,StringIsEmpty</lang>

</lang>