- may_apply(CODE REF, SCALAR)
-
"may_apply($f, $v)" is "$f ? $f->($v) : $v"
- may_apply(CODE REF, SCALAR, SCALAR)
-
"may_apply($f, $v, $otherwise)" is "$f ? $f->($v) : $otherwise"
- if_(BOOL, LIST)
-
special constructs to workaround a missing perl feature:
"if_($b, "a", "b")" is "$b ? ("a", "b") : ()"
example of use: "f("a", if_(arch() =~ /i.86/, "b"), "c")" which is not the
same as "f("a", arch()=~ /i.86/ && "b", "c")"
- if__(SCALAR, LIST)
-
if_ alike. Test if the value is defined
- fold_left { CODE } LIST
-
if you don't know fold_left (aka foldl), don't use it ;p
fold_left { $::a + $::b } 1, 3, 6
gives 10 (aka 1+3+6)
- mapn { CODE } ARRAY REF, ARRAY REF, ...
-
map lists in parallel:
mapn { $_[0] + $_[1] } [1, 2], [2, 4] # gives 3, 6
mapn { $_[0] + $_[1] + $_[2] } [1, 2], [2, 4], [3, 6] gives 6, 12
- mapn_ { CODE } ARRAY REF, ARRAY REF, ...
-
mapn alike. The difference is what to do when the lists have not the same
length: mapn takes the minimum common elements, mapn_ takes the maximum list
length and extend the lists with undef values
- find { CODE } LIST
-
returns the first element where CODE returns true (or returns undef)
find { /foo/ } "fo", "fob", "foobar", "foobir"
gives ``foobar''
- any { CODE } LIST
-
returns 1 if CODE returns true for an element in LIST (otherwise returns 0)
any { /foo/ } "fo", "fob", "foobar", "foobir"
gives 1
- every { CODE } LIST
-
returns 1 if CODE returns true for every element in LIST (otherwise returns 0)
every { /foo/ } "fo", "fob", "foobar", "foobir"
gives 0
- map_index { CODE } LIST
-
just like "map", but set $::i to the current index in the list:
map_index { "$::i $_" } "a", "b"
gives ``0 a'', ``1 b''
- each_index { CODE } LIST
-
just like "map_index", but doesn't return anything
each_index { print "$::i $_\n" } "a", "b"
prints ``0 a'', ``1 b''
- grep_index { CODE } LIST
-
just like "grep", but set $::i to the current index in the list:
grep_index { $::i == $_ } 0, 2, 2, 3
gives (0, 2, 3)
- find_index { CODE } LIST
-
returns the index of the first element where CODE returns true (or throws an exception)
find_index { /foo/ } "fo", "fob", "foobar", "foobir"
gives 2
- map_each { CODE } HASH
-
returns the list of results of CODE applied with $::a (key) and $::b (value)
map_each { "$::a is $::b" } 1=>2, 3=>4
gives ``1 is 2'', ``3 is 4''
- grep_each { CODE } HASH
-
returns the hash key/value for which CODE applied with $::a (key) and $::b
(value) is true:
grep_each { $::b == 2 } 1=>2, 3=>4, 4=>2
gives 1=>2, 4=>2
- partition { CODE } LIST
-
alike "grep", but returns both the list of matching elements and non matching elements
my ($greater, $lower) = partition { $_ > 3 } 4, 2, 8, 0, 1
gives $greater = [ 4, 8 ] and $lower = [ 2, 0, 1 ]
- before_leaving { CODE }
-
the code will be executed when the current block is finished
# create $tmp_file
my $b = before_leaving { unlink $tmp_file };
# some code that may throw an exception, the "before_leaving" ensures the
# $tmp_file will be removed
- cdie(SCALAR)
-
aka conditional die. If a "cdie" is catched, the execution continues
after the cdie, not where it was catched (as happens with die & eval)
If a "cdie" is not catched, it mutates in real exception that can be catched
with "eval"
cdie is useful when you want to warn about something weird, but when you can
go on. In that case, you cdie ``something weird happened'', and the caller
decide wether to go on or not. Especially nice for libraries.
- catch_cdie { CODE1 } sub { CODE2 }
-
If a "cdie" occurs while executing CODE1, CODE2 is executed. If CODE2
returns true, the "cdie" is catched.