Builtins

This topic is meant to document builtins in Pile

Overview

A builtin is an operation that is built into Pile's interpreter. Generally they are more complex compared to the standard operations (like +, -, ?). Builtins can have various use cases and help the developer to create programs with basic features.

I/O

Builtin	Description
`open`	( path -- file )	Pops a `path` as a string and opens a the file located in it and pushes the corresponding `file` object.
`read`	( file -- xs )	Pops a `file` object on the stack and reads until EOF and pushes the read content as a string.
`readline`	( file -- line )	Pops a `file` object on the stack and reads until the end of the line and pushes the read line as a string.
`write`	( file xs -- )	Pops a `file` object on the stack and writes the specified content `xs` as a string.

Typing and conversion

Builtin	Description
`tostring`	Converts the last element on the stack to a `string`.
`tofloat`	Converts the last element on the stack to a `float`. If the conversion fails, it pushes a `nil` value instead.
`toint`	Converts the last element on the stack to a `int`. If the conversion fails, it pushes a `nil` value instead.
`typeof`	Pops the last item on the stack and pushes the name of the respective type of the item in question as a `string`.

Environment and System

Builtin	Description
`exit`	Halts the execution of the program and exits with the exit code at the top of the stack.

Strings

Builtin	Description
`chr`	Pops the last item on the stack (an integer) and interprets it as a character and pushes the corresponding `string` on top of the stack.
`ord`	Pops a string of size 1 on top of the stack and pushes the character code as `int` back on the stack.

Sequences

Builtin	Description
`len`	Pops a sequence on the top of the stack and pushes its size back.