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(guile.info)Type predicates

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Type predicates
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These C functions mirror Scheme's type predicate procedures with one
important difference.  The C routines return C boolean values (0 and 1)
instead of `SCM_BOOL_T' and `SCM_BOOL_F'.

The Scheme notational convention of putting a `?' at the end of
predicate procedure names is mirrored in C by placing `_p' at the end
of the procedure.  For example, `(pair? ...)' maps to `gh_pair_p(...)'.

 - Function: int gh_boolean_p (SCM VAL)
     Returns 1 if VAL is a boolean, 0 otherwise.

 - Function: int gh_symbol_p (SCM VAL)
     Returns 1 if VAL is a symbol, 0 otherwise.

 - Function: int gh_char_p (SCM VAL)
     Returns 1 if VAL is a char, 0 otherwise.

 - Function: int gh_vector_p (SCM VAL)
     Returns 1 if VAL is a vector, 0 otherwise.

 - Function: int gh_pair_p (SCM VAL)
     Returns 1 if VAL is a pair, 0 otherwise.

 - Function: int gh_procedure_p (SCM VAL)
     Returns 1 if VAL is a procedure, 0 otherwise.

 - Function: int gh_list_p (SCM VAL)
     Returns 1 if VAL is a list, 0 otherwise.

 - Function: int gh_inexact_p (SCM VAL)
     Returns 1 if VAL is an inexact number, 0 otherwise.

 - Function: int gh_exact_p (SCM VAL)
     Returns 1 if VAL is an exact number, 0 otherwise.