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is_list                                                   (listSyntax)
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is_list : (term -> bool)

SYNOPSIS
Tests a term to see if it is a list.

DESCRIBE
{is_list} returns {true} of a term representing a list. Otherwise it returns
{false}.

FAILURE
Never fails.

SEEALSO
listSyntax.mk_list, listSyntax.dest_list, listSyntax.mk_cons,
listSyntax.dest_cons, listSyntax.is_cons.

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