Draft:Formaldehyde

Formaldehyde is an esoteric programming language by User:AnalysisOfVariance in 2026 based on Iterate.

Overview

There is a tree that starts with one node.

Structures

() is a plain scope. []. {}. <>.

Structure	Description
~	Creates a new child node and moves the scope's focus to the child node. When the scope ends, the selected node goes back to the parent.
;	Loops forever.
:	Loops N times where N is the index of the current node using breadth-first search from the root.

Commands

Command	Description
Tree operations
<	Move to the previous index node using breadth-first search. If the currently selected node is the root, then the last node is selected.
>	Move to the node with the next index using breadth-first search. If the currently selected node is the last node, then the root is selected.
Loop/scope operations
'	Breaks out of the current scope.
I/O commands
!	Outputs the current node's index starting from zero using breadth-first search from the root as an integer.
$	Outputs the current node's index starting from zero using breadth-first search from the root as a UTF-32 codepoint modulo the maximum valid Unicode character's codepoint plus one.

Examples

XKCD Random Number

~( @ 0
  ~( @ 1
    ~( @ 2
      ~( @ 3
        ~( @ 4
          !
        )
      )
    )
  )
)

Truth-machine

!:(;(!))

See also

• Mhm!
• Iterate