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is_let                                                    (boolSyntax)
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is_let : term -> bool

SYNOPSIS
Tests a term to see if it is a {let}-expression.

DESCRIBE
If {tm} is a term of the form {LET M N}, then {dest_let tm}
returns {true}. Otherwise, it returns {false}.

FAILURE
Never fails.

EXAMPLE

- Term `LET f x`;
<<HOL message: inventing new type variable names: 'a, 'b>>
> val it = `LET f x` : term

- is_let it;
> val it = true : bool

- is_let (Term `let x = P /\ Q in x \/ x`);
> val it = true : bool




SEEALSO
boolSyntax.mk_let, boolSyntax.dest_let.

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