5
| Designed by | User:Fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff | 
|---|---|
| Appeared in | 2024 | 
| Memory system | Basically Everything | 
| Computational class | Turing complete | 
| Major implementations | [1] | 
| Dialects | 15, 35 | 
| File extension(s) | .5,.five | 
5 is an esolang by User:Fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff that is based off the simple fact that 1 = 5. Some programming languages such as Forte support this functionality, but 5 dials it up to 55. Every digit 1 is replaced by the digit 5, even in the program counter. It contains an accumulator, however it also has a queue and a control stack.
Commands
| Command | What it does do | 
|---|---|
| number | set accumulator to number | 
| « | digitwise left shift by 1 (decimal) | 
| » | digitwise right shift by 1 | 
| + | increment accumulator | 
| ² | square accumulator. | 
| ³ | cube accumulator | 
| ! | skip next command if accumulator is 0 | 
| ? | Enqueue the accumulator | 
| - | decrement accumulator | 
| { | push the pc on the stack | 
| | | pop the stack | 
| } | pop the stack and jump to it | 
| ~ | bitwise not | 
| [ | jump to matching ] | 
| * | rotate queue left | 
| ^ | rotate queue right | 
| , | count the 5's in the accumulator | 
| ; | skip next | 
If the accumulator is less than 0, dequeue the top element and set to the accumulator.
Variants
15
15 (or 55) is just 5 with I/O and comments
Comments are in parentheses.
comments are removed before executing
`string` prints out string.
`` prints a newline
# output number @ input $ output char
35
35 is 15 without the 1 = 5 Rule. Backslashes apply the 1 = 5 rule for one instruction.
Programs
Hello, World!
35
`Hello, World!`
Truth-machine
15
;_@{#!}
35
@{#!}
Computation class
You can compile ALWCIDFEC into 5, so 5 is turing complete.
Start with ???
Cell-based instructions
+ ::= «+ * ::= *«+^ 4 ::= ^«+* - ::= » / ::= *»^ 1 ::= ^»*
15 & 35
Since 15 and 35 are supersets of 5, they are turing complete as well.
Loops
brackets can be made like this:
!;[{code!}|;]
Categories
While 5 has no IO, 15 and 35 do.