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Factor handbook > The language > Words > Deferred words and mutual recursion

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Vocabulary
words

Error description
This error is thrown in two cases, and the debugger's summary message reflects the cause:
A word was executed before being compiled. For example, this can happen if a macro is defined in the same compilation unit where it was used. See Compilation units for a discussion.
A word defined with DEFER: was executed. Since this syntax is usually used for mutually-recursive word definitions, executing a deferred word usually indicates a programmer mistake.


Definition