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parents                                                       (Theory)
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parents : string -> string list

SYNOPSIS
Lists the parent theories of a named theory.

DESCRIBE
If {s} is the name of the current theory or an ancestor of the
current theory, the call {parents s} returns a list of strings that
identify the parent theories of {s}. The shorthand {"-"} may be
used to denote the name of the current theory segment.

FAILURE
Fails if the named theory is not an ancestor of the current theory.

EXAMPLE

- parents "bool";
> val it = ["min"] : string list

- parents "min";
> val it = [] : string list

- current_theory();
> val it = "scratch" : string

- parents "-";
> val it = ["list", "option"] : string list




SEEALSO
Theory.ancestry, Theory.current_theory.

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