2020-04-15 00:04:09 +10:00
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Flow
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Note about flow words: flow words can only be used in
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definitions. In the INTERPRET loop, they don't have the desired
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effect because each word from the input stream is executed
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immediately. In this context, branching doesn't work.
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2020-04-17 05:07:31 +10:00
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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.
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(cont.)
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