Initial commit

README.md

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+# ZSH higher order functions
+
+
+You can look at [this article<sup>†</sup>](http://yannesposito.com/Scratch/en/blog/Higher-order-function-in-zsh/) to have more informations.
+
+To install just clone it to `~/.zsh/functional` and add
+
+    # Load functions
+    func_reps=( ~/.zsh/functional/src )
+    for rep in $func_reps; do
+        fpath=($rep $fpath)
+        autoload -U $rep/*(:t)
+    done
+
+to your `.zshrc`

src/filter

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+#!/usr/bin/env zsh
+# usage:
+#
+# $ baz() { print $1 | grep baz }
+# $ filter baz titi bazaar biz
+# bazaar
+# filter() {
+    (($#<1)) && {
+        {
+            print -- "usage: filter func list"
+            print 
+            print -- "example:"
+            print -- '    > baz(){print "$*" | grep baz}'
+            print -- '    > filter baz titi bazaar biz'
+            print -- '    bazaar'
+        } >&2
+        return 1
+    }
+    local predicate=$1
+    local result
+    typeset -a result
+    shift
+    for elem in $@; do
+        if eval $predicate $elem >/dev/null; then
+            result=( $result $elem )
+        fi
+    done
+    print $result
+# }

src/fold

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+#!/usr/bin/env zsh
+    if (($#<2)) {
+        {
+        print -- 'usage: fold function list'
+        print 
+        print -- 'example:'
+        print -- '    > bar() { print $(($1 + $2)) }' 
+        print -- '    > fold bar 0 1 2 3 4 5' 
+        print -- '    15'
+        } >&2
+        return 1
+    }
+    if (($#<3)) {
+        print -- $2
+        return 0
+    } else {
+        local acc
+        local right
+        local func_name=$1
+        local init_value=$2
+        local first_value=$3
+        shift 3
+        right=$( fold $func_name $init_value $@ )
+        acc=$( eval "$func_name $first_value $right" )
+        print -- $acc
+        return 0
+    }

src/map

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+#!/usr/bin/env zsh
+
+map() {
+    (($#<1)) && {
+            print -- "usage: map funcname [list]"
+            print 
+            print -- 'example:'
+            print -- '    > foo(){print "x: $1"}'
+            print -- '    > map foo a b c d'
+            print -- '    x: a'
+            print -- '    x: b'
+            print -- '    x: c'
+            print -- '    x: d'
+            return 1
+        }
+    local func_name=$1
+    shift
+    for elem in $@; print -- $(eval $func_name $elem)
+}