Lexis.allowed_term_constant : string -> bool
STRUCTURE
SYNOPSIS
Tests if a string has a permissible name for a term constant.
DESCRIPTION
When applied to a string, allowed_term_constant returns true if the string is a permissible constant name for a term, that is, if it is an identifier (see the DESCRIPTION for more details), and false otherwise.
FAILURE
Never fails.
EXAMPLE
The following gives a sample of some allowed and disallowed constant names:
   - map Lexis.allowed_term_constant ["pi", "@", "a name", "+++++", "10"];
   > val it = [true, true, false, true, false] : bool list

COMMENTS
Note that this function only performs a lexical test; it does not check whether there is already a constant of that name in the current theory.
SEEALSO
HOL  Kananaskis-14