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MAP_FIRST                                                   (Tactical)
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MAP_FIRST : (('a -> tactic) -> 'a list -> tactic)

SYNOPSIS
Applies first tactic that succeeds in a list given by mapping a function over a
list.

KEYWORDS
theorem-tactical, list.

DESCRIBE
When applied to a tactic-producing function {f} and an operand list
{[x1,...,xn]}, the elements of which have the same type as {f}’s domain
type, {MAP_FIRST} maps the function {f} over the list, producing a list of
tactics, then tries applying these tactics to the goal till one succeeds.
If {f(xm)} is the first to succeed, then the overall effect is the same
as applying {f(xm)}. Thus:

   MAP_FIRST f [x1,...,xn] = (f x1) ORELSE ... ORELSE (f xn)




FAILURE
The application of {MAP_FIRST} to a function and tactic list fails iff
the function does when applied to any of the elements of the list. The
resulting tactic fails iff all the resulting tactics fail when
applied to the goal.

SEEALSO
Tactical.EVERY, Tactical.FIRST, Tactical.MAP_EVERY, Tactical.ORELSE.

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