Empty string: Difference between revisions

=={{header|6502 Assembly}}==

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

<lang 6502>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.

<lang 6502asm>lda #<EmptyString ;address of string we wish to check

sta $00

lda #>EmptyString

sta $01

ldy #0

ldx #0

getStringLength:

lda ($00),y

beq Terminated

iny

jmp getStringLength

Terminated:

cpy #0

beq StringIsEmpty ;if this branch is taken, the string is empty

;otherwise, the string is not empty</lang>