mruby-mruby/mrbgems/mruby-struct/README.md

mruby-struct

This mrbgem provides the Struct class, a convenient way to bundle a number of attributes together, much like Ruby's core Struct class. It allows you to create simple classes (structs) with a defined set of accessor methods for these attributes.

Functionality

• Define new Struct classes with a specific set of members.
• Create instances of these Structs.
• Access and assign to struct members using accessor methods or by index/symbol.
• Iterate over members and values.
• Convert structs to Arrays or Hashes.

Basic Usage

# Define a new Struct class
Point = Struct.new(:x, :y)

# Create an instance of the Point struct
origin = Point.new(0, 0)

# Access attributes
puts origin.x  # Output: 0
puts origin[:y] # Output: 0

# Set attributes
origin.x = 10
origin[:y] = 20

puts origin.inspect # Output: #<struct Point x=10, y=20>

# Another example
Customer = Struct.new("Customer", :name, :address)
joe = Customer.new("Joe Smith", "123 Maple, Anytown NC")

puts joe.name    # Output: Joe Smith
puts joe.address # Output: 123 Maple, Anytown NC

Available Methods

Instances of classes created with Struct.new have several useful methods, including:

• members: Returns an array of symbols representing the names of the instance variables.
• each: Calls a block for each attribute, passing the value.
• each_pair: Calls a block for each attribute, passing the name (symbol) and value.
• select: Returns an array containing values for which the block returns true.
• to_a / values: Returns an array containing the values of the struct.
• to_h: Returns a hash mapping member names (symbols) to their values.
• length / size: Returns the number of members in the struct.
• dig: Extracts a nested value specified by a sequence of keys.
• ==, eql?: For comparing struct instances.

For more details on specific methods, please refer to the mruby documentation or the core Ruby Struct class documentation, as mruby-struct aims for compatibility.