is

get derivative type with given prototype

Parameters

is type :type
   prototype :dictionary :block

Returns

  • :type

Examples

copy
define :animal [
    init: constructor [nick :string age :integer]
    
    speak: method [][
        print "..."
    ]
]

define :fish is :animal []

define :cat is :animal [
    speak: method [][
        print [~"|this\nick|:" "'meow!'"]
    ] 
]                                                   

a: to :cat []
; >> Runtime | cannot initialize object of type :cat
;      error | wrong number of parameters: 0
;            | expected: 2 (nick, age)

scooby: to :animal ["Scooby" 7]
scooby\speak
; ...

bubble: to :fish ["Bubble" 1]            
bubble\speak
; ...

snowflake: to :cat ["Snowflake" 3]
snowflake\speak
; Snowflake: 'meow!'

Related