Class: Decoding::Decoders::Enum

Inherits:

Decoding::Decoder

• Object
• Decoding::Decoder
• Decoding::Decoders::Enum

Defined in:

lib/decoding/decoders/enum.rb

Overview

A decoder for a value that must be one of a fixed set of values.

Values are compared for equality, not with the === operator the Match decoder uses, so the values are read as themselves rather than as patterns.

See Also:

• enum

Instance Method Summary

• #call(value) ⇒ Decoding::Result<Object>
• #initialize(value, *values) ⇒ Enum constructor

  A new instance of Enum.

Methods inherited from Decoding::Decoder

#failure, #to_decoder

Constructor Details

#initialize(value, *values) ⇒ Enum #initialize(values) ⇒ Enum

Returns a new instance of Enum.

Overloads:

• #initialize(value, *values) ⇒ Enum

  Parameters:

  • value (Object)
  • values (Object)
• #initialize(values) ⇒ Enum

  Parameters:

  • values (Array<Object>) —

    the values as a single array

Raises:

• (ArgumentError) —

  when no values are given, or one is repeated.

# File 'lib/decoding/decoders/enum.rb', line 21

def initialize(value, *values)
  @values = collect(value, values)
  super()
end

Instance Method Details

#call(value) ⇒ Decoding::Result<Object>

Parameters:

• value (Object)

Returns:

• (Decoding::Result<Object>)

# File 'lib/decoding/decoders/enum.rb', line 28

def call(value)
  return ok(value) if @values.include?(value)

  err(failure("expected one of #{@values.map(&:inspect).join(", ")}, got #{value.inspect}"))
end