Crystal Plus

An extension of the Crystal standard library.

Installation

Add this to your application's shard.yml:

dependencies:
  crystal_plus:
    github: mosop/crystal_plus

Index

• Dir
  • .tmp : makes a uniquely-named and temporary directory
• NamedTuple
  • #to_h? : is a safe to_h
  • #merge : merges two named tuples
• String
  • #empty_to_nil : returns nil if empty

Dir

.tmp

Makes a uniquely-named directory and yields a passed block with the directory's path. The directory is to be deleted before this method returns.

Dir.tmp do |dir|
  # The dir argument points to a new temporary directory.
end
# The directory is already deleted here.

Parameters

• base : a base directory's path whose a temporary directory will be created (default: "/tmp")
• cleanup : whether to delete a created temporary directory before .tmp returns (default: true)

NamedTuple

#to_h?

def test_to_h(**options)
  options.to_h
end

test_to_h # compile error

require "cyrstal_plus/named_tuple/#to_h?"

def test_to_h?(**options)
  options.to_h?
end

test_to_h? # => nil

#merge

require "cyrstal_plus/named_tuple/#merge"

def merge(tuple, **options)
  tuple.merge(options)
end

def reverse_merge(tuple, **options)
  options.merge(tuple)
end

smile = {face: ":)"}
frown = {face: ":("}
other = {other: ":P"}

merge(smile)          # => {face: ":)"}
merge(smile, **frown) # => {face: ":("}
merge(smile, **other) # => ArgumentError
reverse_merge(smile)  # => ArgumentError

String

#empty_to_nil

Returns nil if self is empty. Otherwise, self.

require "cyrstal_plus/string/#empty_to_nil"

"abc".empty_to_nil # => "abc"
"".empty_to_nil # => nil

Release Notes

• v0.1.2
  • String#empty_to_nil
• v0.1.1
  • Dir.tmp

Contributing

1. Fork it ( https://github.com/mosop/crystal_plus/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request

Contributors

• mosop - creator, maintainer