cation-defined (&quot;external&quot;) functions have ID numbers which are greater than this constant.</P>
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When the Parser reads an identifier token whose position indicates that it is a function, it converts the identifier to a function token (containing a function ID). The parser first checks to see if the identifier is the name of a built-in function. If so, it looks up the function's ID number and stores it in the function token.</P>
<P>
If the identifier is not the name of a built-in function, the P