Moar

An assortment of useful functions.

The docs can be found at https://hexdocs.pm/moar

Installation

The package can be installed by adding moar to your list of dependencies in mix.exs:

def deps do
  [
    {:moar, "~> 1.19"}
  ]
end

Similar libraries

• Bunch
• Swiss

A quick tour

Moar.Assertions

• assert_eq is a pipeable equality assertion, with options such as the ability to ignore order when comparing lists, ignore whitespace when comparing strings, returning a different value than what was passed in, and asserting that a value is within some delta (which can be a number or time duration).
• assert_recent asserts that a datetime is pretty close to now.
• assert_that asserts that a pre-condition and post-condition are true after performing an action.
• refute_that asserts that a condition didn’t change after performing an action.

Moar.Atom

• from_string and to_string convert between strings and atoms, and don’t fail if you try to convert an atom to an atom or a string to a string.

Moar.DateTime and Moar.NaiveDateTime

• add and subtract can add and subtract a Moar.Duration, which is a tuple with a time unit, like {27, :minute}.
• from_iso8601! raises if the string is not in ISO 8601 format.
• to_iso8601_rounded converts to an ISO 8601 string, truncated to the second.
• utc_now takes plus and minus options to get the current time plus or minus some duration.

Moar.Difference

• a protocol that defines diff(a, b) along with implementations for datetimes.

Moar.Duration

• is a {time, unit} tuple (like {27, :minute}) and supports the regular t:System.time_unit/0 values and also :minute, :hour, and :day.
• ago returns the duration between a given datetime and now.
• approx shifts the duration to a simple approximate value.
• between returns the duration between two datetimes.
• convert converts a duration to a new time unit, returning only the value.
• format formats a duration in long ("3 seconds") or short ("3s") format with optional transformers and suffix.
• from_now returns a duration between now and a given datetime.
• humanize converts the duration to the highest possible time unit.
• shift, shift_up, and shift_down convert a duration to a new time unit.
• to_string renders a duration into a string like "27 minutes".

Moar.Enum

• at is like Enum.at but raises if the index is out of bounds.
• compact rejects nil values.
• first! returns the first item or raises if there isn’t a first item.
• isort and isort_by sort case-insensitively.
• tids extracts tid fields. (tid is short for “test id” and the authors of Moar use tids extensively for testing.)

Moar.File

• new_tempfile_path returns a new path for a tempfile, without creating it.
• write_tempfile writes some data to a new tempfile.

Moar.Map

• atomize_key, atomize_keys, and deep_atomize_keys convert keys in a map from strings to atoms, and stringify_keys does the opposite.
• merge and deep_merge merge maps, and can also convert enumerables into maps before merging.
• rename_key and rename_keys rename keys in a map.
• transform transforms a key or multiple keys with a transformer function.

Moar.Opts

• is meant to be used with function options.
• get extracts a value from opts, falling back to a default if the value is blank (via Moar.Term.blank?/1)
• take extracts multiple values from opts, falling back to defaults if the value is blank (via Moar.Term.blank?/1)

Moar.Protocol

• implements! raises if a struct does not implement the given protocol.
• implements? returns true if a struct implements the given protocol.

Moar.Random

• integer returns a random integer.
• string returns random base64- or base32-encoded string.

Moar.Retry

• rescue_until and rescue_for run the given function repeatedly until it does not raise.
• retry_until and retry_for run the given function repeatedly until it returns a truthy value.

Moar.String

• append_unless_blank appends a suffix to a string, unless the string is blank.
• inner_truncate removes the middle of a string to make it the desired length.
• secure_compare compares two strings in constant time.
• slug converts a string into a slug with a custom joiner character; dasherize and underscore are shortcuts for common slug formats.
• squish collapses consecutive whitespace characters.
• surround wraps a string with the given characters.
• to_case converts text to :camel_case, :lower_camel_case, or :snake_case.
• to_integer converts a string to an integer with a few handy options.
• trim is like String.trim/1 but handles nil values.
• truncate_at truncates a string at the last instance of a substring that results in the truncated string being shorter than a given length.

Moar.Sugar

• error, noreply, and ok create tuples ("foo" |> error() -> {:error, "foo"}).
• error! and ok! unwrap tuples ({:error, "foo"} |> error!() -> "foo").
• returning takes two arguments and returns the second one.

Moar.Term

• blank? returns true if a term is nil, an empty string, a whitespace-only string, an empty list, or an empty map.
• present? is the opposite of blank?.
• presence returns a default if the argument is blank.

Moar.Tuple

• from_list! converts a list of tuples like [{:ok, 1}, {:ok, 2}, {:ok, 3}] to a tuple like {:ok, [1, 2, 3]}
• reduce converts a list of tuples like [{:ok, 1}, {:error, 2}] to a map like %{ok: [1], error: [2]}