MDK::Common::Func - miscellaneous functions
use MDK::Common::Func qw(:all);
may_apply($f, $v) is $f ? $f->($v) : $v
may_apply($f, $v)
$f ? $f->($v) : $v
may_apply($f, $v, $otherwise) is $f ? $f->($v) : $otherwise
may_apply($f, $v, $otherwise)
$f ? $f->($v) : $otherwise
special constructs to workaround a missing perl feature: if_($b, "a", "b") is $b ? ("a", "b") : ()
if_($b, "a", "b")
$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")
f("a", if_(arch() =~ /i.86/, "b"), "c")
f("a", arch()=~ /i.86/ && "b", "c")
if_ alike. Test if the value is defined
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)
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 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
returns the first element where CODE returns true (or returns undef)
find { /foo/ } "fo", "fob", "foobar", "foobir"
gives "foobar"
returns 1 if CODE returns true for an element in LIST (otherwise returns 0)
any { /foo/ } "fo", "fob", "foobar", "foobir"
gives 1
returns 1 if CODE returns true for every element in LIST (otherwise returns 0)
every { /foo/ } "fo", "fob", "foobar", "foobir"
gives 0
just like map, but set $::i to the current index in the list:
map
$::i
map_index { "$::i $_" } "a", "b"
gives "0 a", "1 b"
just like map_index, but doesn't return anything
map_index
each_index { print "$::i $_\n" } "a", "b"
prints "0 a", "1 b"
just like grep, but set $::i to the current index in the list:
grep
grep_index { $::i == $_ } 0, 2, 2, 3
gives (0, 2, 3)
returns the index of the first element where CODE returns true (or throws an exception)
find_index { /foo/ } "fo", "fob", "foobar", "foobir"
gives 2
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"
returns the hash key/value for which CODE applied with $::a (key) and $::b (value) is true:
grep_each { $::b == 2 } 1=>2, 3=>4, 4=>2
gives 1=>2, 4=>2
alike grep, but returns both the list of matching elements and non matching elements
my ($greater, $lower) = partition { $_ > 3 } 4, 2, 8, 0, 1
gives $greater = [ 4, 8 ] and $lower = [ 2, 0, 1 ]
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
aka conditional die. If a cdie is catched, the execution continues after the cdie, not where it was catched (as happens with die & eval)
cdie
If a cdie is not catched, it mutates in real exception that can be catched with eval
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.
If a cdie occurs while executing CODE1, CODE2 is executed. If CODE2 returns true, the cdie is catched.
MDK::Common
To install MDK::Common, copy and paste the appropriate command in to your terminal.
cpanm
cpanm MDK::Common
CPAN shell
perl -MCPAN -e shell install MDK::Common
For more information on module installation, please visit the detailed CPAN module installation guide.