Keyword Reference

Text between curly braces ({}) represent blocks. A block is a sequence of instructions encased in curly braces in source code.

{
    "This is a block!" printLine
}

Text between less than and greater than symbols (<>) represent identifiers in source code.

# These are all valid identifiers
foo
_bar
baz13

Text between square brackets ([]) is optional.

Stack Operations

Name	Signature	Description
`dup`	`a -- a a`	Duplicates `a`.
`pop`	`a --`	Pops `a` off of the stack.

Name	Signature	Description
`+`	`a b -- c`	Returns the sum of `a` and `b`.
`-`	`a b -- c`	Returns `a` minus `b`.
`*`	`a b -- c`	Returns the product of `a` and `b`.
`/`	`a b -- c`	Returns `a` divided by `b`.
`%`	`a b -- c`	Returns `a` modulo `b`. See modular arithmetic.

Name	Signature	Description
`=`	`a b -- c`	Returns true if `a` and `b` are equal. Returns false otherwise.
`<`	`a b -- c`	Returns true if `a` is less than `b`. Returns false otherwise.
`<=`	`a b -- c`	Returns true if `a` is less than or equal to `b`. Returns false otherwise.
`>`	`a b -- c`	Returns true if `a` is greater than `b`. Returns false otherwise.
`>=`	`a b -- c`	Returns true if `a` is greater than or equal to `b`. Returns false otherwise.
`not`	`a -- b`	Returns the opposite of `a`. `a` must be a boolean.

Name	Signature	Description
`toBool`	`a -- b`	Converts `a` into a boolean value.
`toNum`	`a -- b`	Converts `a` into a numeric value.
`toString`	`a -- b`	Converts `a` into a string.

Name	Signature	Description
`assert`	`a --`	Halts execution of the program if `a` is false.
`assertEqual`	`a b --`	Halts execution of the program if `a` and `b` are not equal.
`assertNotEqual`	`a b --`	Halts execution of the program if `a` and `b` are equal.

Name	Signature	Description
`getElement`	`list index -- elem`	Returns the element from a list `list` at index `index`.

Name	Signature	Description
`print`	`a --`	Writes contents of `a` to stdout.
`printLine`	`a --`	Writes contents of `a` to stdout with a trailing newline character.
`readLine`	`-- input`	Returns a single line of input from stdin.
`waitMore`	`a --`	Halts execution of the program for `a` seconds. `a` must be a float.

Name	Signature	Description
`const <name>`	`a --`	Creates a constant with the name `<name>` and a value of `a`.
`var <name>`	`--`	Creates a variable with the name `<name>`.
`set <name>`	`a --`	Assigns the value of `a` to a variable with the name `<name>`.
`<name>`	`-- a`	Pushes the value of a variable or constant with the name `<name>` onto the stack.

Name	Signature	Description
`while {body}`	`a --`	Continually executes the instructions in `{body}` so long as `a` is true.
`fnn <name> {body}`	`--`	Creates a new function with the name `<name>`.
`if {body} [else {else-body}]`	`a --`	Conditionally executes the instructions in `{body}` if `a` is true, otherwise the instructions in `{else-body}` are executed.
`<name>`	Unknown	Executes instructions in the body (`{body}`) of a function with the name `<name>`.

Name	Signature	Description
`file <file-path>`	`--`	Includes the contents of another Stacko file at `<file-path>`.