promote collect macro as a map+filter replacement (#15788)

* promote `collect` macro as a map+filter replacement

* Update lib/pure/collections/sequtils.nim
This commit is contained in:
Miran
2020-10-30 10:12:01 +01:00
committed by GitHub
parent c0fdc8b215
commit ec059240b0
2 changed files with 29 additions and 1 deletions

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@@ -27,6 +27,7 @@
## languages.
##
## For functional style programming you have different options at your disposal:
## * `sugar.collect macro<sugar.html#collect.m%2Cuntyped%2Cuntyped>`_
## * pass `anonymous proc<manual.html#procedures-anonymous-procs>`_
## * import `sugar module<sugar.html>`_ and use
## `=> macro<sugar.html#%3D>.m,untyped,untyped>`_
@@ -45,8 +46,14 @@
## let
## foo = toSeq(1..10).map(x => x*2).filter(x => x mod 6 != 0)
## bar = toSeq(1..10).mapIt(it*2).filterIt(it mod 6 != 0)
## baz = collect(newSeq):
## for i in 1..10:
## let j = 2*i
## if j mod 6 != 0:
## j
##
## doAssert foo == bar
## doAssert foo == baz
## echo foo # @[2, 4, 8, 10, 14, 16, 20]
##
## echo foo.any(x => x > 17) # true
@@ -361,7 +368,11 @@ proc map*[T, S](s: openArray[T], op: proc (x: T): S {.closure.}):
## Since the input is not modified you can use it to
## transform the type of the elements in the input container.
##
## Instead of using `map` and `filter`, consider using the `collect` macro
## from the `sugar` module.
##
## See also:
## * `sugar.collect macro<sugar.html#collect.m%2Cuntyped%2Cuntyped>`_
## * `mapIt template<#mapIt.t,typed,untyped>`_
## * `apply proc<#apply,openArray[T],proc(T)_2>`_ for the in-place version
##
@@ -424,7 +435,11 @@ iterator filter*[T](s: openArray[T], pred: proc(x: T): bool {.closure.}): T =
## Iterates through a container `s` and yields every item that fulfills the
## predicate `pred` (function that returns a `bool`).
##
## Instead of using `map` and `filter`, consider using the `collect` macro
## from `sugar` module.
##
## See also:
## * `sugar.collect macro<sugar.html#collect.m%2Cuntyped%2Cuntyped>`_
## * `fliter proc<#filter,openArray[T],proc(T)>`_
## * `filterIt template<#filterIt.t,untyped,untyped>`_
##
@@ -444,7 +459,11 @@ proc filter*[T](s: openArray[T], pred: proc(x: T): bool {.closure.}): seq[T]
## Returns a new sequence with all the items of `s` that fulfilled the
## predicate `pred` (function that returns a `bool`).
##
## Instead of using `map` and `filter`, consider using the `collect` macro
## from `sugar` module.
##
## See also:
## * `sugar.collect macro<sugar.html#collect.m%2Cuntyped%2Cuntyped>`_
## * `filterIt template<#filterIt.t,untyped,untyped>`_
## * `filter iterator<#filter.i,openArray[T],proc(T)>`_
## * `keepIf proc<#keepIf,seq[T],proc(T)>`_ for the in-place version
@@ -560,7 +579,11 @@ template filterIt*(s, pred: untyped): untyped =
## the predicate needs to be an expression using the ``it`` variable
## for testing, like: ``filterIt("abcxyz", it == 'x')``.
##
## Instead of using `mapIt` and `filterIt`, consider using the `collect` macro
## from `sugar` module.
##
## See also:
## * `sugar.collect macro<sugar.html#collect.m%2Cuntyped%2Cuntyped>`_
## * `fliter proc<#filter,openArray[T],proc(T)>`_
## * `filter iterator<#filter.i,openArray[T],proc(T)>`_
##
@@ -916,7 +939,11 @@ template mapIt*(s: typed, op: untyped): untyped =
## The template injects the ``it`` variable which you can use directly in an
## expression.
##
## Instead of using `mapIt` and `filterIt`, consider using the `collect` macro
## from `sugar` module.
##
## See also:
## * `sugar.collect macro<sugar.html#collect.m%2Cuntyped%2Cuntyped>`_
## * `map proc<#map,openArray[T],proc(T)>`_
## * `applyIt template<#applyIt.t,untyped,untyped>`_ for the in-place version
##

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@@ -59,12 +59,13 @@
## * `unicode module<unicode.html>`_ for Unicode UTF-8 handling
## * `sequtils module<sequtils.html>`_ for operations on container
## types (including strings)
## * `parsecsv module<parsecsv.html>`_ for a high-performance CSV parser
## * `parseutils module<parseutils.html>`_ for lower-level parsing of tokens,
## numbers, identifiers, etc.
## * `parseopt module<parseopt.html>`_ for command-line parsing
## * `pegs module<pegs.html>`_ for PEG (Parsing Expression Grammar) support
## * `strtabs module<strtabs.html>`_ for efficient hash tables
## (dictionaries, in some programming languages) mapping from strings to strings
## * `pegs module<pegs.html>`_ for PEG (Parsing Expression Grammar) support
## * `ropes module<ropes.html>`_ for rope data type, which can represent very
## long strings efficiently
## * `re module<re.html>`_ for regular expression (regex) support