11 lines
245 B
Forth
11 lines
245 B
Forth
[undefined] var [if] .( var is undefined at first check) cr [then]
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marker forget-var
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variable var
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[defined] var [if] .( var is defined at second check) cr [then]
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forget-var
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[undefined] var [if] .( var is undefined at third check) cr [then]
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