README

Underscore4d

This project makes an effort to add functional algorithms that are available in most modern languages (JS, C#, C++) and native in functional languages, but are generally not available in Delphi yet. Spring4d adds a lot of this functionality for IEnumerable<T>, but are still not available for builtin Delphi types like TList<T>.

Underscore4d adds functions in the style of UnderscoreJS, using the _ namespace and passing both list/enumerable and the (anonymous) function to perform.

(Be aware that there's a performance penalty when using this library, as the supplied anonymous functions will not be inlined into the algorithm.)

UnderscoreJS	Spring4d	Delphi	Underscore4d
each	ForEach	x
map T	x	x	Map
map T,S	OfType?	x	Map
reduce T	Aggregate T	x	Reduce
reduce T,S	x	x	Reduce
reduceRight	x	x
find	First	x	Find*
find noexcept	FirstOrDefault	x	FindOrDefault
filter	Where	x	Filter
where
findWhere
reject
every	All	x	Every
some	Any
contains	Contains	Contains	x
pluck
max T			Max*
min T			Min*
sortBy
groupBy
indexBy
countBy
shuffle
sample
toArray
size
partition
first	[0]	First
initial
last		Last
rest
compact
flatten
without
union	Union	x	Union
intersection	IntersectWith	x	Intersection
difference		x	Difference
uniq			Uniq
zip		x	Zip
unzip
object
chunk
indexOf
lastIndexOf
sortedIndex
findIndex
findLastIndex
range

*) will throw exception on failure

Extra functions

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