Functions

Declare a function

Use ktFunction() to declare a function. Use returns {} to configure its return type, then type {} and reference() to specify that type. Use body {} for its implementation and literal() for a literal value.

import com.alexstyl.prosakt.ktFile

val source = ktFile {
    ktFunction("greeting") {
        returns {
            type {
                reference("String")
            }
        }
        body {
            literal("Hello")
        }
    }
}

Generated Kotlin:

fun greeting(): String {
    return "Hello"
}

With an explicit non-Unit return type, Prosa.kt returns the last expression in body {} automatically.

Add a parameter

Use parameter() inside ktFunction {} to add a parameter. Pass its name as the argument. Use type {} and reference() inside the parameter block to specify its type. Use reference() in the function body to refer to the parameter.

import com.alexstyl.prosakt.ktFile

val source = ktFile {
    ktFunction("greeting") {
        parameter("name") {
            type {
                reference("String")
            }
        }
        returns {
            type {
                reference("String")
            }
        }
        body {
            reference("name")
        }
    }
}

Generated Kotlin:

fun greeting(name: String): String {
    return name
}

Supply a default value

Use default {} inside the parameter block to generate a default argument. Use literal() inside it for a literal value.

import com.alexstyl.prosakt.ktFile

val source = ktFile {
    ktFunction("greeting") {
        parameter("name") {
            type {
                reference("String")
            }
            default {
                literal("World")
            }
        }
        returns {
            type {
                reference("String")
            }
        }
        body {
            reference("name")
        }
    }
}

Generated Kotlin:

fun greeting(name: String = "World"): String {
    return name
}

Call parameter() again for each additional parameter; their order is preserved. Use modifier("vararg") in a parameter block to add the vararg keyword. Constructor parameters also support type {} and default {}; see Classes.

Generate a statement

Use call() inside body {} to generate a function call. Use argument {} to provide an argument. Omit returns {} for a function with an implicit Unit return type.

import com.alexstyl.prosakt.ktFile

val source = ktFile {
    ktFunction("printGreeting") {
        body {
            call("println") {
                argument {
                    literal("Hello")
                }
            }
        }
    }
}

Generated Kotlin:

fun printGreeting() {
    println("Hello")
}

For a function without an implementation, set modifiers = listOf("abstract") in a valid abstract context, such as an interface.