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singleton_of_list                                                (Lib)
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singleton_of_list : 'a list -> 'a

SYNOPSIS
Turns a single-element list into a singleton.

DESCRIBE
{singleton_of_list [x]} returns {x}.

FAILURE
Fails if applied to a list that is not of length 1.

SEEALSO
Lib.pair_of_list, Lib.triple_of_list, Lib.quadruple_of_list.

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