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<H2><A NAME="SLang_is_defined"></A> <A NAME="s79">79. <B>SLang_is_defined</B></A></H2>

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<DT><B> Synopsis </B><DD><P>Check to see if the interpreter defines an object
<DT><B> Usage </B><DD><P><CODE>int SLang_is_defined (char *nm)</CODE>
<DT><B> Description </B><DD><P>The <CODE>SLang_is_defined</CODE> function may be used to determine
whether or not a variable or function whose name is given by
<CODE>em</CODE> has been defined.  It returns zero if no such object has
been defined.  Othewise it returns a non-zero value whose meaning
is given by the following table:
<BLOCKQUOTE><CODE>
<PRE>
      1    intrinsic function  (SLANG_INTRINSIC)
      2    user-defined slang function (SLANG_FUNCTION)
     -1    intrinsic variable (SLANG_IVARIABLE)
     -2    user-defined global variable (SLANG_GVARIABLE)
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</CODE></BLOCKQUOTE>
<DT><B> See Also </B><DD><P><CODE>SLadd_intrinsic_function, SLang_run_hooks, SLang_execute_function</CODE>
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