String length: Difference between revisions

20 PRINT LEN a$</lang>

However, it's not quite as trivial as this.

==Byte length==

Strings can contain embedded colour codes; an inline INVERSE (CAPS SHIFT + 4) would be represented as CHR$ 20 + CHR$ 1. The LEN function will account for all these bytes. On the flipside, ZX Spectrum keywords are all tokenised, and there's nothing stopping you using them in a string; " RANDOMIZE ", if the keyword is used, will take a single byte (CHR$ 249) rather than the 11 characters it actually uses. The above version of the code will produce byte length.

==Character length==

Stripping out all entries in the string with codes in the lower 32 will get rid of colour codes. The character length of a token is not a simple thing to determine, so this version strips them out too by eliminating anything above CHR$ 164 (the last UDG). A 91-entry DATA list of token lengths might be the next step.

<lang zxbasic>10 INPUT a$

20 LET b$=""

30 FOR x=1 TO LEN a$

40 LET k=CODE a$(x)

50 IF k<32 OR k>164 THEN GOTO 70

60 LET b$=b$+a$(k)

70 NEXT x

80 PRINT LEN b$</lang>