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left.for
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C **********************************************************************
C * *
C * LEFT$ - RETURN LEFTMOST N CHARACTERS OF STRING S$ *
C * *
C * FROM MBASIC. RETURN LEFTMOST CHARACTERS OF THE STRING. FOR *
C * EXAMPLE: *
C * *
C * S$ = NEW$(12) *
C * CALL STRPUT(S$,'HELLO, WORLD',12) *
C * T$ = LEFT$(S$,2) *
C * *
C * T$ NOW HAS 'HE' *
C * *
C **********************************************************************
C
REAL FUNCTION LEFT$(S$, N)
REAL S$
INTEGER N
C
REAL D$
INTEGER ID$(2), D$OFF, D$LEN
REAL R$
INTEGER IR$(2), R$OFF, R$LEN
C
EQUIVALENCE (D$, ID$(1)), (ID$(1), D$OFF), (ID$(2), D$LEN)
EQUIVALENCE (R$, IR$(1)), (IR$(1), R$OFF), (IR$(2), R$LEN)
C
D$ = S$
R$ = S$
R$LEN = 0
IF (N .LE. 0) GO TO 1
R$LEN = D$LEN
IF (N .GE. D$LEN) GO TO 1
R$LEN = N
1 LEFT$ = R$
RETURN
END