// control.asm:	WORD p_if,'IF',fasm

anchor:p_if[]

=== Word: IF

....
Data stack: Compiling: ( -- a )
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"IF" is an immediate function word that is used together with
<<p_else,ELSE>> and <<p_then,THEN>> to implement structured execution
control. IF results in layout of a <<p_0branch,0BRANCH>> instruction
with an unresolved branch offset, and places the address for resolving
this instruction on the datastack. This address will then be resolved
and asssigned by a subsequent <<p_else,ELSE>> or <<p_then,THEN>> so
that at execution time there is an appropriate conditional branch past
the "then-part" of the "structured statement".