Loops/Increment loop index within loop body: Difference between revisions

=={{header|RPL}}==

<code>BPRIM?</code> is defined at [[Primality by trial division#RPL|Primality by trial division]]

RPL allows to modify both increment and index within a <code>FOR..NEXT</code> loop:

≪ 0

42 1E15 '''FOR''' j

IF j R→B <span style="color:blue">BPRIM?</span> THEN

1 + DUP 1 DISP

j DUP 2 DISP

'''ELSE''' 1 '''END'''

'''IF''' OVER 42 == '''THEN''' 1E15 'j' STO '''END'''

'''STEP'''

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It is nevertheless more idiomatic to use a <code>WHILE..REPEAT</code> loop:

≪ 0 42

'''WHILE''' OVER 12 < '''REPEAT'''

'''IF''' DUP R→B <span style="color:blue">BPRIM?</span> THEN

SWAP 1 + DUP 1 DISP SWAP

DUP 2 DISP DUP

'''ELSE''' 1 '''END''' +

'''END''' DROP

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