Operators

Operators

Combinator(s)	w/ Result	Stateful	w/ Result	Notes
Control.Lens (Getting)
view / ^.		use		View a single target, or fold multiple monoidal targets.
views		uses		View/fold after applying a function.
to				Build a getter from a plain function.
Control.Lens (Setting)
set / .~	<.~	assign / .=	<.=	Replace target(s) with value. <<.~ and <<.= return the old value.
over / %~	<%~	%=	<%=	Replace target(s) by applying function. <<%~ and <<%= return the old value
setting , upon				Build a setter from a map-like function.
id / %%~ / traverseOf		%%=		Update target(s) with an Applicative or auxiliary result.
Control.Lens.Fold / Control.Lens.Prism
review / #		reuse		Choose a branch of a sum type
preview / ^? / firstOf		preuse		Get the first target or Nothing if there are no targets.
previews		preuses		preview after applying a function
toListOf / ^..				Return a list of the target(s)
itoListOf / ^@..				Return a list of (index,target) pairs.
Control.Lens (Getting Indexed)
iview / ^@.		iuse		View the index and value of an IndexedGetter or IndexedLens.
iviews		iuses		View a function of the index and value of an IndexedGetter into the current environment.
Control.Lens (Setting Indexed)
iset / .@~		.@=		Set target(s) with access to the index.
iover / %@~	<%@~	%@=	<%@=	Update target(s) with access to the index.
withIndex, itraverseOf, %%@~		%%@=		Update target(s) with an Applicative or auxiliary result with access to the index.
Control.Lens (math)
+~	<+~	+=	<+=	Add to target(s)
-~	<-~	-=	<-=	Subtract from target(s)
*~	<*~	*=	<*=	Multiply target(s)
//~	<//~	//=	<//=	Divide target(s)
^~	<^~	^=	<^=	Raise target(s) to a non-negative Integral power
^^~	<^^~	^^=	<^^=	Raise target(s) to an Integral power
**~	<**~	**=	<**=	Raise target(s) to an arbitrary power
Control.Lens (logic)
||~	<||~	||=	<||=	Logically or target(s)
&&~	<&&~	&&=	<&&=	Logically and target(s)
<>~	<<>~	<>=	<<>=	mappend to the target monoidal value(s)
Data.Bits.Lens
.|.~	<.|.~	.|.=	<.|.=	Bitwise or target(s)
.&.~	<.&.~	.&.=	<.&.=	Bitwise and target(s)
System.FilePath.Lens
</>~	<</>~	</>=	<</>=	Append a relative path to a FilePath
<.>~	<<.>~	<.>=	<<.>=	Append a file extension to a FilePath