17 lines
708 B
Plaintext
17 lines
708 B
Plaintext
Flow
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Note that flow words can only be used in definitions. In the
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INTERPRET loop, they don't have the desired effect because each
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word from the input stream is executed immediately. In this
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context, branching doesn't work.
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f IF A ELSE B THEN: if f is true, execute A, if false, execute
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B. ELSE is optional.
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BEGIN .. f UNTIL: if f is false, branch to BEGIN.
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BEGIN .. AGAIN: Always branch to BEGIN.
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x y DO .. LOOP: LOOP increments y. if y != x, branch to DO.
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x CASE y OF A ENDOF z OF B ENDOF C ENDCASE: If x == y, execute
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A, if x == z, execute B. Otherwise, execute C. x is dropped
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in case of an OF match, *but it is kept if it reaches C*. You
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have to consume it to avoid PSP leak. (cont.)
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