Title: Types and Features for Object Oriented Programming
Version: 0.1.0
Description: Construct message-passing style objects with types and features. Q7 types uses composition instead of inheritance in creating derived types, allowing defining any code segment as feature and associating any feature to any object. Compared to R6, Q7 is simpler and more flexible, and is more friendly in syntax.
License: GPL-3
Encoding: UTF-8
LazyData: true
RoxygenNote: 7.1.1
Depends: magrittr
Suggests: knitr, rmarkdown, testthat
VignetteBuilder: knitr
NeedsCompilation: no
Packaged: 2020-11-23 14:20:23 UTC; ELATI
Author: Siqi Zhang ORCID iD [aut, cre], Bayer HealthCare [fnd]
Maintainer: Siqi Zhang <iqis.gnahz@gmail.com>
Repository: CRAN
Date/Publication: 2020-11-25 10:00:06 UTC

Pipe operator

Description

See magrittr::%>% for details.

Usage

lhs %>% rhs

Clone

Description

Clone

Usage

clone(...)

Arguments

...

dot-dot-dot

Clone an Instance

Description

Clone an Instance

Usage

## S3 method for class 'Q7instance'
clone(inst, deep = TRUE, ...)

Arguments

inst

Q7 object instance

deep

to copy nested object instances recursively; Boolean

...

dot-dot-dot

Value

Q7 object instance

Examples


Type1 <- type(function(num){
  print_num <- function(){
    base::print(num)
  }
})
myType1 <- Type1(1)
myType1$print_num()
myType1_clone <- clone(myType1)
myType1_clone$print_num()

Extend a Type upon a (Proto)type

Description

Used only inside a type definition

Usage

extend(prototype)

Arguments

prototype

Q7type; function

Value

localized Q7type; function

Examples


Type1 <- type(function(arg1){
    val1 <- arg1
    get_val1 <- function(){
         val1
    }
}, "Type1")

Type2 <- type(function(arg1, arg2){
    extend(Type1)(arg1)
    val2 <- arg2
    get_val2 <- function(){
        val2
    }
}, "Type2")

myType2 <- Type2("foo", "bar")

myType2$get_val1()
myType2$get_val2()

Create an Object Feature

Description

Create an Object Feature

Usage

feature(expr)

Arguments

expr

expression

Value

a Q7 feature

Examples


Type1 <- type(function(num){})

hasMagic <- feature({
    change_number <- function(){
        num + 1
    }
})

myType1 <- Type1(1) %>% hasMagic()
myType1$change_number()


# Use S3 method dispatch for different behaviors
hasMagic <- feature_generic(s3 = "hasMagic")

hasMagic.Type1 <- feature({
    change_number <- function(){
        num + 1
    }
})

hasMagic.Type2 <- feature({
    change_number <- function(){
        num - 1
    }
})

Type1 <- type(function(num){},
              s3 = "Type1") %>%
    hasMagic()

Type2 <- type(function(num){},
              s3 = "Type2") %>%
    hasMagic()

myType1 <- Type1(1)
myType1$change_number()

myType2 <- Type2(1)
myType2$change_number()

Create a Generic Feature

Description

Use this function when you need to create more than one methods for Q7 types with different S3 classes. The s3 field and the feature's name should be the same.

Usage

feature_generic(s3, ...)

Arguments

s3

S3 Class of the feature

...

dot-dot-dot

Value

a generic Q7 feature

See Also

feature

Implement any Feature for an Object

Description

Implement any Feature for an Object

Usage

implement(obj, feat)

Arguments

obj

Q7 object (type or instance)

feat

Q7 feature or expression

Value

Q7 object (type or instance)

Examples


Type1 <- type(function(num){})

myType1 <- Type1(1) %>% implement({
    change_number <- function(){
        num + 1
    }
})

myType1$change_number()

Is it a Q7 Type, Instance or Feature?

Description

Is it a Q7 Type, Instance or Feature?

Usage

is_type(x)

is_instance(x)

is_feature(x)

Arguments

x

object

Value

Boolean

Build a Q7 Object Instance from a List

Description

Build a Q7 Object Instance from a List

Usage

list2inst(x, s3 = "default", parent = parent.frame(), ...)

Arguments

x

list

s3

S3 class name of the instance

parent

parent environment of the instance

...

dot-dot-dot

Value

Q7 object instance

Examples

my_data <- list(a = 1,
                add_to_a = function(value){
                  .my$a <- a + value
                })

myDataObject <- list2inst(my_data)

myDataObject$a
myDataObject$add_to_a(20)
myDataObject$a

Make a Localized Copy of a Q7 Type or Instance

Description

Make a Localized Copy of a Q7 Type or Instance

Usage

localize(obj, envir = parent.frame())

Arguments

obj

Q7 type or instance

envir

environment

Value

function

Merge all Members of Two Instances

Description

All public and private members of instance 2 will be copied to instance 1, overwriting any of the same names.

Usage

merge(inst1, inst2)

Arguments

inst1

instance to move members to

inst2

instance to move members from

Value

Q7 instance, with environment identity of inst1 and members from both instances.

Examples


Screamer <- type(function(words){
  scream <- function(){
    paste0(paste(words,
                 collapse = " "),
           "!!!")
  }
})

Whisperer <- type(function(words){
  whisper <- function(){
    paste0("shhhhhhh.....",
           paste(words,
                 collapse = " "),
           "...")
  }
})

p1 <- Screamer("I love you")
p1$scream()

p2 <- Whisperer("My parents came back")
p2$whisper()

p1 <- p1 %>% merge(p2)

# note the the "word" for both methods became that of p2
p1$whisper()
p1$scream()

Create a Q7 Type

Description

Create a Q7 Type

Usage

type(x = function() {
}, s3 = "Q7default")

Arguments

x

function or expression; becomes the definition of the object

s3

S3 class for the object; necessary when using S3 generic functions

Value

Q7 type; function

Examples


Adder <- type(function(num1, num2){
    add_nums <- function(){
        num1 + num2
    }
 })

myAdder <- Adder(1, 2)
myAdder$add_nums()