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[ 0 => '{{infobox proglang', 1 => '|name=☭', 2 => '|paradigms=imperative<br>turing tarpit', 3 => '|author=[[User:Dragoneater67|Dragoneater67]]', 4 => '|year=[[:Category:2026|2026]]', 5 => '|memsys=[[:Category:Cell-based|Cell-based]]', 6 => '|dimensions=one-dimensional', 7 => '|class=[[:Category:Turing complete|Turing complete]]', 8 => '|majorimpl=[https://pastebin.com/sJR24nnN C++]', 9 => '|influence=[[Sharp_flat|#b]]<br>[[!I!M!P!O!S!S!I!B!L!E!]]<br>[[Brainfuck]]', 10 => '|files=<code>.hammerandsickle</code>', 11 => '}}', 12 => ''''☭''' is a [[Turing complete|turing complete]] [[Esoteric programming language|esoteric programming language]]. The goal of the language is to make doing trivial operations nearly impossible.', 13 => '==Overview==', 14 => 'The language is separated into 2 phases of execution. The overview is very brief as it is hard to explain the workings of ☭. Refer to the reference implementation to get a better understanding of the language.', 15 => '===Phase 1===', 16 => 'Phase 1 reads the source string character-by-character and executes a command. Before each command is executed g is regenerated using LCG (the initial seed for g is <math>89404137</math>). The command is determined by this formula (<math>c</math> is the current character, <math>i</math> is the position of the current character):<br>', 17 => '<math>\left(\left(\left((c \oplus q) + (i \bmod 3) + (g \gg 24)\right) \bmod 3\right) + 3\right) \bmod 3</math>', 18 => '{| class="wikitable"', 19 => '! Selector !! Type !! Operation', 20 => '|-', 21 => '| style="text-align:center;" | '''0'''', 22 => '| State mutation', 23 => '| Mutates internal accumulators and shifts keys:', 24 => '* <tt>a += 3</tt>', 25 => '* <tt>w += 7</tt>', 26 => '* <tt>q -= 43</tt> (Input key rotation)', 27 => '* <tt>p -= 13</tt> (Memory pointer shift)', 28 => '* <tt>g ^= 0xCAFEBABE</tt> (PRNG scramble)', 29 => '|-', 30 => '| style="text-align:center;" | '''1'''', 31 => '| State mutation', 32 => '| Mutates internal accumulators and shifts keys:', 33 => '* <tt>a -= 2</tt>', 34 => '* <tt>w -= 5</tt>', 35 => '* <tt>q += 67</tt> (Input key rotation)', 36 => '* <tt>p += 17</tt> (Memory pointer shift)', 37 => '* <tt>g += a ^ w</tt> (PRNG mix)', 38 => '|-', 39 => '| style="text-align:center;" | '''2'''', 40 => '| Instruction generation', 41 => '| Synthesizes a candidate byte <tt>b</tt> using the formula:', 42 => '<math>b = \neg \left( \left( (a \lor w) \land h \right) \oplus q \oplus (g \land \text{0xFF}) \right)</math><br>', 43 => 'If <tt>b</tt> is a valid instruction (<tt>*</tt>, <tt>#</tt>, or <tt>?</tt>), it is appended to the Phase 2 instruction tape.<br>', 44 => 'If <tt>b</tt> is invalid, the PRNG is penalized (<tt>g = 0xDEADBEEF</tt>).', 45 => '|}', 46 => '===Phase 2===', 47 => 'Phase 2 is a virtual machine that executes the bytecode generated in phase 1.', 48 => 'The virtual machine has:', 49 => '* The memory tape with the length of <math>10^6</math> bytes', 50 => '* The instruction tape with the length of <math>2^{31}-1</math> bytes', 51 => '* The memory pointer', 52 => '* The instruction pointer', 53 => 'The memory pointer is initially pseudorandom (derived from the source string), while the instruction pointer is always initialized to <math>0</math>. Instructions are single ASCII characters, any other ASCII character is an invalid character and will result in an error. Here is a quick overview of available commands:', 54 => '{| class="wikitable"', 55 => '! Instruction !! Condition !! Operation', 56 => '|-', 57 => '| rowspan="2" style="text-align:center; font-family:monospace; font-size:1.2em;" | *', 58 => '| Instruction pointer is '''Odd'''', 59 => '| Adds 251 to the current memory cell, then moves the memory pointer forward by 999983 positions.', 60 => '|-', 61 => '| Instruction pointer is '''Even'''', 62 => '| Reads a byte from input, XORs it with register <tt>q</tt>, and stores it in the current memory cell, then jumps back 2 steps.', 63 => '|-', 64 => '| rowspan="2" style="text-align:center; font-family:monospace; font-size:1.2em;" | #', 65 => '| Current memory cell is '''0'''', 66 => '| Jumps back 7 steps, then modifies the instruction at that location by cycling it (<tt>*</tt> → <tt>#</tt> → <tt>?</tt> → <tt>*</tt> → ...).', 67 => '|-', 68 => '| Current memory cell is '''not 0'''', 69 => '| Moves the memory pointer backward by 999979 positions, then adds 241 to the current memory cell.', 70 => '|-', 71 => '| rowspan="2" style="text-align:center; font-family:monospace; font-size:1.2em;" | ?', 72 => '| Memory pointer is '''Odd'''', 73 => '| Outputs the character at the current memory cell XORed with register <tt>h</tt>, then adds 239 to the current memory cell.', 74 => '|-', 75 => '| Memory pointer is '''Even'''', 76 => '| If current memory cell is 0, skip forward 13 instructions. Otherwise, set both memory pointer and the instruction pointer to pseudo-random values derived from <tt>g</tt>.', 77 => '|}', 78 => 'The virtual machine has the following internal registers:', 79 => '* a (phase 1 only, does not affect the state of the virtual machine)', 80 => '* w (phase 1 only, does not affect the state of the virtual machine)', 81 => '* h (the rolling encryption key for output)', 82 => '* q (the rolling encryption key for input)', 83 => '* p (the memory pointer)', 84 => '* j (the instruction count)', 85 => '* y (the instruction pointer)', 86 => '* g (pseudo-random value)', 87 => 'After each instruction is executed the new <tt>h</tt> is calculated using this formula (<math>t_p</math> is current memory cell value and <math>b_y</math> is the current instruction):<br>', 88 => '<math>h_{new} = ((g \gg 16) \land \text{0xFF}) \oplus h \oplus (t_p \land (b_y \lor q))</math>', 89 => '==Computational class==', 90 => '☭ as mentioned earlier, is [[Turing complete|turing complete]], but may be considered a [[Turing tarpit|turing tarpit]] by some.', 91 => '* The <tt>*</tt> and <tt>#</tt> instructions allow for arbitrary arithmetic operations since they can increment values of memory cells', 92 => '* The <tt>?</tt> and <tt>#</tt> instructions allow for complex control flow because of conditional jumps and self-modifying code', 93 => '* The <tt>*</tt> and <tt>?</tt> instructions allow for input/output operations, although not required for [[Turing completeness|turing completeness]], they are still very useful for some use cases (such as printing "Hello world!")', 94 => '==Examples==', 95 => 'No ☭ program has been discovered yet.', 96 => '==External resources==', 97 => '* [https://pastebin.com/sJR24nnN Reference implementation written in C++]', 98 => '', 99 => '[[Category:Turing tarpits]] ', 100 => '[[Category:Low-level]] ', 101 => '[[Category:Cell-based]] ', 102 => '[[Category:Implemented]] ', 103 => '[[Category:Languages]]', 104 => '[[Category:2026]]', 105 => '[[Category:Turing complete]]' ]