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`class SymbolicHash`

A hash which forces all keys to be symbols and fails with KeyError when strings are used.

Definitions

`def [](key)`

Fetch a value using a symbolic key.

Signature

parameter　key　String | Symbol: The lookup key.
returns　Object | Nil: The associated value.
raises　KeyError: If key is a string.

Implementation

def [] key
	raise KeyError.new("attribute #{key} is a string, prefer a symbol") if key.is_a? String
	super key.to_sym
end

`def []=(key, value)`

Assign a value after coercing its key to a symbol.

Signature

parameter　key　String | Symbol: The lookup key.
parameter　value　Object: The value to assign.
returns　Object: The assigned value.

Implementation

def []= key, value
	super key.to_sym, value
end

`def fetch(key, *arguments, &block)`

Fetch a value after coercing the key to a symbol.

Signature

parameter　key　String | Symbol: The lookup key.
parameter　arguments　Array: The arguments.
yields　{|key| ...}: The missing symbolic key when no default argument is given.
returns　Object: The associated, default, or block-provided value.

Implementation

def fetch(key, *arguments, &block)
	key = key.to_sym
	
	super
end

`def include?(key)`

Check whether this collection includes the given value.

Signature

parameter　key　String | Symbol: The lookup key.
returns　Boolean: Whether the symbolic key exists.

Implementation

def include? key
	key = key.to_sym
	
	super
end