Lcl · Core · Packages · Libraries

Dict

namespace Dict

Basic associative container (dictionary) for Lcl.

Supports reader syntax for direct construction.

proc Dict::new *values

Constructs a dict from a list of arguments.

The arguments are taken as key-values.

Examples:

>> Dict::new x 1 y 2
#{"x" 1 "y" 2}
>> len [Dict::new a 1 b 2]
2
>> get [Dict::new a 1 b 2] "a"
1

proc Dict::keys d

Return the keys of a dictionary as a list. Note that order is not guaranteed.

Keys are copied.

Examples:

>> Dict::keys #{a 1 b 2 c 3}
("b" "a" "c")

proc Dict::values d

Return the values of a dictionary as a list. Note that order is not guaranteed.

Values are copied.

Examples:

>> Dict::values #{a 1 b 2 c 3}
(2 1 3)

proc Dict::items d

Return the key, value pairs of a dictionary as an associative list.

Items are copied.

Examples:

>> Dict::items #{a 1 b 2 c 3}
(("b" 2) ("a" 1) ("c" 3))

proc Dict::merge a b

Merges two dictionaries together. When values conflict, the second dictionary takes preference over the first.

Returns a new dictionary.

Examples:

>> let d1 #{a 1 b 2}
>> let d2 #{b 20 c 30}
>> Dict::merge $d1 $d2
#{"b" 20 "a" 1 "c" 30}

proc Dict::map d fn

Applies the function over a dictionary. The function is two-valued and applied on each key-value pair.

Returns a new dictionary.

Examples:

>> Dict::map #{a 1 b 2 c 3} [lambda {k v} {* $v 2}]
#{"b" 4 "a" 2 "c" 6}

proc Dict::filter d fn

Applies the function over a dictionary, creating a new dictionary where the function on key-value pairs produces a truthy value.

Returns a new dictionary.

Examples:

>> Dict::filter #{a 1 b 2 c 3} [lambda {k v} {> $v 1}]
#{"b" 2 "c" 3}

proc Dict::reduce d init fn

Applies a function over the key-value pairs, passing an accumulator and return the end result with an initializer. Does not mutate the dictionary.

Examples:

>> Dict::reduce #{a 1 b 2 c 3} 0 [lambda {acc k v} {+ $acc $v}]
6