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is_arb                                                    (boolSyntax)
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is_arb : term -> bool

SYNOPSIS
Tests a term to see if it’s an instance of {ARB}.

LIBRARY
boolSyntax

DESCRIBE
Returns {true} if and only if {M} has the form {ARB}.

USES
None known.

SEEALSO
boolSyntax.mk_arb, boolSyntax.dest_arb.

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