Variable

The bridge between ParameterSpec and PropertySpec.

The goal of Variable

ParameterSpec and PropertySpec are very similar:

ParameterSpec	PropertySpec
name	name
modifiers	modifiers
type	type
defaultValue	initializer
null	mutable: Boolean

Although they have more fields, these are the ones KotlinPoetDSL supports before V0.2.

Because they are this similar it would make sense to pass around a type that has the commonalities of both the classes. In KotlinPoetDSL, this class is called Variable.

Constructions

There are 3 function-names: of, valOf, varOf. These can all be invoked the same way. Therefor I show below only using valOf.

val clazz = ClassName("", "Clazz")

"a" valOf String::class // val a : String
"a" valOf clazz //val  a: Clazz

// S surrounds string with quotes
"a".valOf<String>("Hi %L".S(), "you") // val a : String = "Hi you"
"a".valOf(clazz, "%T()", clazz)      // a: Clazz = Clazz()

 // will be supported in V0.2
//"a".valOf(String::class, "Hi %L", "you") // val a : String = "Hi you"

for the vararg:

"a" vararg String::class //vararg a  : String
"a" vararg clazz // vararg a : Clazz

  // will be supported in V0.2 for varargVal and varargVar
 //  "a" varargVal String::class //vararg a : String
//   "a" varargVal clazz        // vararg a : Clazz

Interoperability

Slightly interoperable, but will be improved in V0.2

Creating Variables

val param = ParameterSpec
    .builder("hi", String::class, KModifier.PUBLIC, KModifier.OPEN)
    .defaultValue("hello".S())
    .build()
    .toVariable()
param //public open hi: String = "hello"


val prop = PropertySpec.builder("hi", String::class, KModifier.OPEN)
    .initializer("hello".S())
    .build()
prop // open val hi : String: "hello"

Using Variable

In V0.1 the variables can't be used. In V0.2, the variables can be used interchangeable with ParamSpec and PropertySpec.

Getting KotlinPoetTypes

val t = ("f" varOf String::class)
t.toPropertySpec() // var f : String
t.toParamSpec()   // f : String

The spec passed to the constructor will be returned, so with it's unsuported fields. On the other hand, annotations are not yet support by KotlinPoetDSL, so when you go from one type to another (paramSpec.toVariable().toPropertySpec()), the annotations are not preserved.