10 GO SUB 1000
20 LET e=LEN p$
30 LET a$=p$(ip)
40 IF a$=">" THEN LET dp=dp+1
50 IF a$="<" THEN LET dp=dp-1
60 IF a$="+" THEN LET d(dp)=d(dp)+1
70 IF a$="-" THEN LET d(dp)=d(dp)-1
80 IF a$="." THEN PRINT CHR$ d(dp);
90 IF a$="," THEN INPUT d(dp)
100 IF a$="[" THEN GO SUB 500
110 IF a$="]" THEN LET bp=bp-1: IF d(dp)<>0 THEN LET ip=b(bp)-1
120 LET ip=ip+1
130 IF ip>e THEN PRINT "eof": STOP
140 GO TO 30

499 REM match close
500 LET bc=1: REM bracket counter
510 FOR x=ip+1 TO e
520 IF p$(x)="[" THEN LET bc=bc+1
530 IF p$(x)="]" THEN LET bc=bc-1
540 IF bc=0 THEN LET b(bp)=ip: LET be=x: LET x=e: REM bc will be 0 once all the subnests have been counted over
550 IF bc=0 AND d(dp)=0 THEN LET ip=be: LET bp=bp-1
560 NEXT x
570 LET bp=bp+1
580 RETURN

999 REM initialisation
1000 DIM d(100): REM data stack
1010 LET dp=1: REM data pointer
1020 LET ip=1: REM instruction pointer
1030 DIM b(30): REM bracket stack
1040 LET bp=1: REM bracket pointer
1050 LET p$="++++++++[>++++[>++>+++>+++>+<<<<-]>+>+>->>+[<]<-]>>.>---.+++++++..+++.>>.<-.<.+++.------.--------.>>+.>+++++.": REM program, marginally modified from Wikipedia; outputs CHR$ 13 at the end instead of CHR$ 10 as ZX Spectrum Basic handles the carriage return better than the line feed
1060 RETURN