You're using the latest version of Japt.
▼ Expand all) transpiles to )).
transpiles to ).
Parens left out at ;[]{} or at the beginning or end of the program are auto-inserted.
A-Z are pre-defined variables; see the Variables table for default values.
a-z and à-ÿ are various methods, and transpile to e.g. `.a(; see the Methods tables below.
ABC{ starts an anonymous function with parameters A, B, and C; equivalent to function(A,B,C){.
@ is equivalent to XYZ{, and _ is equivalent to Z{Z.
If a-z or à-ÿ is the first item in a function call, it is interpreted as a method; e.g. Uqs is equivalent to UqX{Xs}.
If an infix operator is the first item in a function call, it is transpiled to function(a,b){return a(operator)b}.
If the above is prefixed by !, it is transpiled to function(a,b){return b(operator)a}.
'a transpiles to "a".
#a transpiles to 97, the char-code of a.
¡ through Þ are shortcuts for common 2+ byte sequences; see the Unicode shortcuts table below.
"abc{U}xyz" transpiles to "abc"+(U)+"xyz".
Japt uses the shoco library for string compression. It can compress almost any string that contains lowercase letters, often saving quite a few bytes. Here's how to use it:
Oc"text" compresses the text.
Od"text" decompresses text.
Using backticks instead of quotes, e.g. `text`, also decompresses the text.
$...$ is evaluated as pure JS.
Any of "`$ left out at the end of the program is auto-inserted, and all parentheses and functions are automatically.
ß is a function that runs the program again with given inputs.
Some methods require a regex, or a string built like a regex. Pure regexes are extremely hard to use because the transpiler doesn't set them aside, like it does with strings. This creates several problems:
- 1. The transpiler thinks a slash is a division sign.
- 2. If you try putting flags on the regex, the transpiler will see them as function calls.
- 3. Good luck successfully getting the transpiler to not mess with the contents of the regex.
Instead, use a string. Strings can be used just like regexes, with a couple extra rules:
- Flags need to be passed in a separate string. In most methods that require regexes, the g flag is on by default. Pass in an empty string to remove it.
- Backslashes \ need to be doubled, or just replaced with %. This means that to get a literal %, you must use %%.
You can use JavaScript's character classes, e.g. %w. A few classes have been added to make regexes golfier. Here's a reference for what the common classes match:
| Class | Chars |
| %w | A-Za-z0-9 |
| %W | Anything else |
| %d | 0-9 |
| %D | Anything else |
| %s | Whitespace |
| %S | Anything else |
| %n | Newline |
| %t | Tab |
| %b | Edge of a word |
| %B | Non-edge |
| %a | a-z |
| %A | A-Z |
| %l | A-Za-z |
| %L | Anything else |
| %p | Printable ASCII |
| %P | Anything else |
| %q | Printable + newline |
| %Q | Anything else |
| %v | AEIOUaeiou |
| %V | Anything else |
| %y | AEIOUYaeiouy |
| %Y | Anything else |
| %c | Consonants + Yy |
| %C | Anything else |
| Var | Value |
| A | 10 |
| B | 11 |
| C | 12 |
| D | 13 |
| E | 14 |
| F | 15 |
| G | 16 |
| H | 32 |
| I | 64 |
| J | -1 |
| K | new Date() |
| L | 100 |
| M | Math |
| N | input |
| O | utils |
| P | "" |
| Q | "\"" |
| R | "\n" |
| S | " " |
| T | 0 |
| U | 1st input |
| V | 2nd input |
| W | 3rd input |
| X | 4th input |
| Y | 5th input |
| Z | 6th input |
If the first character in the program is ;, the following vars are changed:
| Var | Value |
| A | [] |
| B | ALPHABET |
| C | alphabet |
| D | QWERTY |
| E | ASCII |
| F | "[A-Za-z]" |
| G | 36 |
| H | 65 |
| I | 91 |
| J | "," |
| L | "." |
| Var | Value |
| E | Euler's constant (2.71828...) |
| P | pi (3.14159...) |
| Q | golden ratio (1.61803...) |
| R | sqrt(1/2) |
| S | sqrt(2) |
| T | tau (pi * 2) |
Returns atan2(n₁,n₂).
Returns cos(n).
Returns e^n.
Returns the nth Fibonacci number.
Math.hypot; returns the sqrt of the sum of the squares of the inputs.
Returns the natural logarithm of n.
Returns the logarithm of n in base 2.
Returns the logarithm of n in base 10.
Returns a random non-negative integer less than n.
Returns a random multiple of n₃ (relative to n₁) between n₁ and n₂.
Returns a random float between 0 and n.
Returns a random float between n₁ and n₂.
Returns sin(n).
Returns tan(n).
Displays x in an alert box. Equivalent to alert(x).
Compresses s using shoco.
Decompresses s using shoco. For constant strings, wrap in backticks instead, e.g. `compressed`.
Fetchs the data from URL s, calling f on the returned data. Asynchronous.
Logs x to the console. Equivalent to console.log(x).
Appends x to the program output.
Appends x and a newline to the program output.
Clears program output, optionally replacing it with x.
Evaluates s as Japt code and returns the result.
Evaluates s as JavaScript and returns the result.
Returns the last index of s in this, or -1.
Returns the last index i where f(this[i]) returns truthily.
Returns the first index of s in this, or -1.
Returns the first index i where f(this[i]) returns truthily.
Returns the char-code at index n in this.
Like .m(f), but performs on char-codes; "Abc"cX{X+1} -> "Bcd".
Replaces x with y in this for each pair of chars xy in s.
Replaces x with y in this for each pair of args x,y.
Recursively replaces r/s with s in this.
Returns this.match(r/s), or an empty array if there are no matches.
Returns the char at index n in this.
Returns the result of f(this).
Overwrites s onto this at index n.
Inserts s into this at index n.
Removes n₁ chars from this at index n₂.
Removes all characters in s from this, case-insensitive unless x is truthy.
Removes all characters in this that return a truthy value when run through f.
Returns the length of this.
Splits this with s, runs each item through f, then rejoins with s.
Returns parseInt(this,n).
Converts this from base s to decimal ("baab"n"ab" -> "1001"n2 -> 9).
Converts this from base a to decimal ("baab"n['a'b] -> "1001"n2 -> 9).
Converts this from base x to decimal, maps through f, then converts back to base x.
Converts this from base x₁ to base x₂.
Converts this from base x₁ to decimal, maps through f, then converts to base x₂.
Removes all characters not in s from this, case-insensitive unless x is truthy.
Removes all characters in this that return a falsy value when run through f.
Returns this repeated n times.
Returns this + f(this); "ABC"pX{Xv} -> "ABCabc".
Returns this split at occurences of s.
Replaces r with s in this.
Replaces RegExp(s₁,s₃) with s₂ in this. If s₃ contains the g flag, it will be removed, and vice versa.
Returns the section of this from index n₁ to index n₂.
Returns the length-n₂ section of this starting at index n₁.
Converts this to uppercase.
Converts this to lowercase.
Reverses this.
Trims whitespace from the ends of this. If n is 1, trims only the right; if n is 2, trims only the left; otherwise, trims both.
Splits this at newlines, transposes rows with columns, then rejoins with newlines.
Maps each column in this through f.
Splits this at newlines, rotates by n*90 degrees clockwise, then rejoins with newlines.
Returns all combinations of this. If n is specified, only returns the combinations of length n.
Returns all unique permutations of this. If n is specified, returns the unique permutations of length n.
Returns this.search(r/s). Similar to S.b(s), but forces input to be a regex.
Returns an array of all subsections of this of length n. If a is specified, it is prepended to the array beforehand.
Returns an array of all (non-empty) subsections of this, mapping each through f.
Takes each consecutive pair of items x,y in this and maps to f(x,y,x+y). If a is specified, it is prepended to the array beforehand.
Cumulative reduce; like q r, but returns an array of each intermediate value.
Replaces each char in this with s.
Returns the number of matches of r/s in this.
Rotates this n chars to the right.
If n%2 < 1, mirrors this at its last char ("abc"ê -> "abcba"); otherwise, appends the reverse of this ("abc"ê1 -> "abccba").
Returns true if this is a palindrome (i.e. equal to its reverse); false otherwise.
Returns every xth char of this, starting at index y.
Interleaves the strings, concatenating each char in this with the corresponding char in s.
Interleaves the string with the array, concatenating each char in this with the corresponding item in a. If no a is given, uses the index instead.
Same as above, but maps each pair of chars/items through f.
Repeats s until it reaches this.length. "abcde"î"12" -> "12121"
Joins each char in this with each char in s (Cartesian product). If no s is given, reuses this (Cartesian power of 2).
Same as above, but maps each pair of chars through f.
Returns all indices in this where r can be matched. Case-sensitive unless x is truthy.
Sorts the chars of this. If f is given, sorts as if each char has been run through f.
Cuts this into slices of length n. "abcde"ò2 -> ["ab","cd","e"]
Partitions this between chars X, Y where f(X,Y) is truthy. "abba"ò@X<Y} -> ["a","bba"].
Cuts this into n arrays of every nth char. "abcde"ó2 -> ["ace","bd"]
Partitions this between chars X, Y where f(X,Y) is falsy. "abbc"ó@X<Y} -> ["ab","bc"].
Partitions this at chars X where f(X) is truthy. "abca"ô@X>'b} -> ["ab","a"]
Returns a random character of this.
Returns a string of ceil(n) random characters of this (with replacement).
Returns a random permutation of this.
Returns true if this contains s; false otherwise.
Returns true if this contains any element of a; false otherwise.
Left-pads each line of this to the length of the longest with s.
Left-pads each line of this to length n with s.
Right-pads each line of this to the length of the longest with s.
Right-pads each line of this to length n with s.
Center-pads each line of this to the length of the longest with s.
Center-pads each line of this to length n with s.
Groups chars by their value. "bacca"ü -> ["aa","b","cc"]
Groups chars by their value when run through f.
Returns the last index i where f(this[i], i, this) returns truthily.
Returns the last index of x in this, or -1 if x doesn't exist in this.
Returns the first index i where f(this[i], i, this) returns truthily.
Returns the first index of x in this, or -1 if x doesn't exist in this.
Flattens this, i.e. expands all sub-arrays into the main array.
Flattens this by n levels.
Flat-map; map each item in this through f, then flatten the result by 1 level.
Appends a to this.
Maps each item in this through f, then returns true if any are truthy, false otherwise.
Maps each item in this through f, then returns true if all are truthy, false otherwise.
Returns true each element in this is equal to the corresponding element in a and their lengths are the same, false otherwise.
Selects the items in this that return truthily to f.
Selects the items in this that are also in a.
If n%3 === 0, selects the items in this that are also contained in a; if n%3 === 2, selects each item contained in both this and a; if n%3 === 1, selects each item that can be removed from both this and a. Only differs from .f(a) when there are multiple elements.
Returns the item at index n in this.
Maps the item at the given index through f.
Returns the item at the given multi-dimensional index.
Maps the item at the given multi-dimensional index through f.
Returns the items at the given indices.
Maps the items at the given indices through f.
Returns the result of f(this).
Sets the item at index n in this to x.
Inserts x into this at index n.
Removes n₁ items from this at index n₂.
Removes all elements in a from this.
Selects the items in this that return falsily to f.
Removes all occurrences of x from this.
Returns the length of this.
Returns the items in this whose lengths return truthily to f. ["a","bc",""]lX{X<2} -> ["a",""]
Returns the items in this whose lengths equal n (short for l==).
Maps each item in this through f.
Sorts this by passing each pair of items through f. If f(x,y)<0, x is sorted to the left; if f(x,y)>0, y is sorted to the left.
Sorts this lexicographically by alphabet s. ["aa","ab","b","ca","cab"]n"cba" -> ["ca","cab","b","ab","aa"]
Sorts this by the order of items in a. [0,3,6,9]n[8,6,7,5,3,0,9] -> [6,3,0,9]
Removes the last n items of this and returns them.
Maps the last item in this through f.
Appends x to the end of this.
Returns this joined with s.
Reduces this by f. If x is specified, the initial value is set to x, e.g. this.reduce(f,x).
Returns the section of this from index n₁ to index n₂.
Returns the length-n₂ section of this starting at index n₁.
Prepends x to the beginning of this.
Removes the first n items of this and returns them.
Maps the first item of this through f.
Reverses this.
Returns the sum of all items in this. If f is given, each item is mapped through f first.
If this is a 2D array, or an array of strings, transposes rows with columns.
Maps each column in this through f.
If this is a 2D array, or an array of strings, rotates this by n*90 degrees clockwise.
Returns all combinations of the elements of this. If n is specified, only returns the combinations of length n.
Returns all unique permutations of this. If n is specified, returns the unique permutations of length n.
Returns all unique items of this, in original order.
Setwise union; returns all unique items of this concatenated with a, in original order.
Returns an array of all subsections of this of length n. If a is specified, it is prepended to the array beforehand.
Returns an array of all (non-empty) subsections of this, mapping each through f.
Takes each consecutive pair of items x,y in this and maps to f(x,y,x+y). If a is specified, it is prepended to the array beforehand.
Cumulative reduce; like r, but returns an array of each intermediate value.
Returns the first item that returns truthily when run through f.
Fills this with a.
Returns the number of items that return truthily when run through f.
Rotates this n items to the right.
If n%2 < 1, mirrors this at its last char ([1,2,3]ê -> [1,2,3,2,1]); otherwise, appends the reverse of this ([1,2,3]ê1 -> [1,2,3,3,2,1]).
Returns true if this is a palindrome (i.e. equal to its reverse); false otherwise.
Returns every xth item of this, starting at index y.
Converts this from an array of base-n digits to an integer.
Converts this from base-a to an integer (['c,7,7,'c]ì[7,'c] -> [1,0,0,1]ì2 -> 9).
Converts this from base-s to an integer (['c,7,7,'c]ì"7c" -> [1,0,0,1]ì2 -> 9).
Converts this from base x to an integer, maps through f, then converts back to base x.
Converts this from base x₁ to base x₂.
Converts this from base x₁ to an integer, maps through f, then converts to base x₂.
Pairs each item in this with the corresponding item in a. If no a is given, pairs with the index instead.
Same as above, but maps each pair of items through f.
Repeats a until it reaches this.length. [0,1,2,3,4]î[1,2] -> [1,2,1,2,1]
Pairs each item in this with each item in a (Cartesian product). If no a is given, uses this.
Same as above, but maps each pair of items through f.
Returns the indices of all items in this that give a truthy value when run through f.
Returns the indices of all items in this.
Sorts this as if each value has been run through f.
Cuts this into slices of length n. [1,2,3,4,5]ò2 -> [[1,2],[3,4],[5]]
If n is negative, works backward from the end of the array. [1,2,3,4,5]ò2n -> [[1],[2,3],[4,5]]
Partitions this between items X, Y where f(X,Y) is truthy. [1,2,0,3]ò@X>Y} -> [[1,2],[0,3]].
Cuts this into n arrays of every nth item. [1,2,3,4,5]ò2 -> [[1,3,5],[2,4]]
Partitions this between items X, Y where f(X,Y) is falsy. [1,2,0,3]ò@X>Y} -> [[1],[2,0],[3]].
Partitions this at items X where X is falsy. [1,2,0,3]ô -> [[1,2],[3]]
Partitions this at items X where f(X) is truthy. [1,2,3,1]ô@X>2} -> [[1,2],[1]]
Returns a random element of this.
Returns an array of ceil(n) random elements of this (with replacement).
Returns a random permutation of this.
Returns a random item from this which satisfies f.
Returns true if this contains any element of a; false otherwise.
Returns true if this contains x; false otherwise.
Left-pads each item in this to the length of the longest with s.
Left-pads each item in this to length n with s.
Right-pads each item in this to the length of the longest with s.
Right-pads each item in this to length n with s.
Center-pads each item in this to the length of the longest with s.
Center-pads each item in this to length n with s.
Groups items by their value (i.e. [6,1,3,3,6] -> [[1],[3,3],[6,6]].
Groups items by their value when run through f.
Returns the absolute value of this.
Returns the absolute difference between this and n.
Returns this bounded with min n₁ and max n₂.
Returns this rounded up to the nearest multiple of n.
Returns the char at code-point this+n.
Returns this*Math.pow(10,n).
Returns this rounded down to the nearest multiple of n.
Returns the sign of this; -1 for negative values, 1 for positive, 0 for 0, and NaN for NaN.
Compares this with n; -1 if less, 1 if greater, 0 if equal, or NaN if either is NaN.
Returns the item/char at index this in a/s.
Returns the result of running this through f.
Returns this rounded to n significant decimals.
Runs f every this milliseconds.
Runs s as JS every this milliseconds.
Returns true if this is prime; false otherwise.
Returns true if this is coprime to n (no shared factors); false otherwise.
Returns the prime factors of this as an array.
Returns the factorial of this.
Returns the smaller of this and n.
Returns n - this. If no n is given, this returns -this.
Returns an array of all integers in the range [0,this) (or vice-versa). Optionally maps through f.
Returns an array of all integers in the range [this,n) (or vice-versa). Optionally maps through f.
Returns an array of numbers in the range [this,n₁), generated by starting at this and repeatedly adding n₂. Optionally maps through f.
Raises this to the nth power.
Returns the nth root of this.
Returns this rounded to the nearest multiple of n.
Returns this converted to a base-n string (9s2 -> "1001").
Returns this converted to a base-s string (9s"ab" -> "baab").
Returns this converted to a base-a string (9s["ab""tr"] -> "trababtr").
Converts this to a base-x string, runs it through f, and then converts back to base x.
Runs f after this milliseconds.
Runs s as JS after this milliseconds.
Returns the non-negative remainder of this / n; like Python's % operator.
Returns 1 if this is divisible by n; 0 otherwise.
Returns the larger of this and n.
Returns this rounded to n decimals.
Returns the GCD of this and n.
Returns this / n, rounded toward 0.
Returns the number of combinations of [1..this]. If n is specified, only returns the number of combinations of length n.
Returns the number of permutations of [1..this]. If n is specified, returns the number of permutations of length n.
Returns all integer divisors of this. If x is truthy, doesn't include this.
Repeats s this times.
Returns an array of the base-n digits of this; the inverse of A.ì(n). Works for all integer n except 0.
Returns an array of the base-a digits of this (9ì["ab"7] -> [7,"ab","ab",7]).
Returns an array of the base-s digits of this (9ì"ab" -> ["b","a","a","b"]).
Converts this to an array of base-x digits, runs it through f, and then converts back to base x.
Repeats s until it reaches length this. 5î"ab" -> "ababa"
Like o, but inclusive (creates the range [this..n] instead of [this..n)).
Like o, but creates the range [this..this+n) instead of [this..n).
Like ó, but inclusive.
Like o, but creates the range [n₁...this] (with step size of n₂), and the range is not reversed if this is less than n₁.
Maps each integer in [1...this] through f.
Returns a random item of this.o().
Returns an array of ceil(n) random items of this.o() (with replacement).
Returns a random permutation of this.o().
Returns the smallest non-negative integer that returns a truthy value when run through this, mapping through f beforehand.
Returns the smallest integer that returns a truthy value when run through this, starting at n.
Like .a(), but with bijective base-10 integers.
Like .a(), but with all integers, in the order 0, -1, 1, -2, 2, -3...
Like .a(), but with all integers, in the order n, n - 1, n + 1, n - 2, n + 2, n - 3...
Like .a(), but looks for a falsy return value.
Repeatedly appends this(a.g(-1), i, a) to a, then returns the nth item in a.
Like .g(), but returns the first n items in a.
Returns the n₁th item (0-indexed) that returns a truthy value when run through this, starting at n₂.
Returns the first n₁ items that return truthy values when run through this, starting at n₂.
You can use K to get new Date(), or Ð to call new Date(.
If you give these methods a number as a first parameter, it will change the get part of the function according to the following table:
| Input | Function |
| 0 | get |
| 1 | set |
| 2 | getUTC |
| 3 | setUTC |
See MDN for more information on these methods.
Returns this.getMilliseconds().
Returns this.getSeconds().
Returns this.getMinutes().
Returns this.getHours().
Returns this.getDay().
Returns this.getDate().
Returns this.getMonth().
Returns this.getYear().
Returns this.getFullYear().
Returns this.getTime().
Returns this.getTimezoneOffset().
Returns this.toString().
Returns [this.toString(), this.toDateString(), this.toTimeString(), this.toISOString(), this.toGMTString(), this.toUTCString(), this.toLocaleString(), this.toLocaleDateString(), this.toLocaleTimeString()][n]. Some of these methods may not work in all browsers/environments.
Flags are inserted directly into the input box. You can use multiple flags at once, e.g. -Prw.
Map; runs the program on each item in the input, returning an array of the results. If the input is a number, it's turned into a range first; if the input is a string, it's split into chars beforehand and joined again afterwards.
Filter; runs the program on each item in the input, returning an array of only the items that return a truthy value. If the input is a number, it's turned into a range first; if the input is a string, it's split into chars beforehand and joined again afterwards.
A shortcut for -fg; runs the program on each item, returning the first one that returns a truthy value.
Some; runs the program on each item, returning true if any returns a truthy value, false otherwise.
Every; runs the program on each item, returning false if any returns a falsy value, true otherwise.
Returns the first item in the output. If given a number (-g3), returns the nth item.
Returns the last item in the output.
Returns the boolean NOT of the output: true if the output is falsy; false otherwise.
Converts to boolean: returns true if the output is truthy; false otherwise.
Converts the output to a number.
If the output is an array, outputs with no separator (i.e. joined with P).
Prettyprints the output, wrapping strings in quotes and arrays in brackets.
If the output is an array, outputs separated by newlines (i.e. joined with R).
If the output is an array, outputs separated by spaces (i.e. joined with S).
Calls .x() on the output. If the output is an array, sums; if the output is a string, trims whitespace from both ends.
If there's an error, catches it and prints string instead.
If the output is falsy, prints string instead.
| Char | Value |
| ¡ | Um@ |
| ¢ | Us2 |
| £ | m@ |
| ¤ | s2 |
| ¥ | == |
| ¦ | != |
| § | <= |
| ¨ | >= |
| © | && |
| ª | || |
| « | &&! |
| ¬ | q |
| ® | m_ |
| ¯ | s0, |
| ° | ++ |
| ± | += |
| ² | p2 |
| ³ | p3 |
| ´ | -- |
| µ | -= |
| ¶ | === |
| · | qR |
| ¸ | qS |
| ¹ | ) |
| º | (( |
| » | ((( |
| ¼ | .25 |
| ½ | .5 |
| ¾ | .75 |
| À | !== |
| Á | >>> |
| Â | ~~ |
| Ã | } |
| Ä | +1 |
| Å | s1 |
| Æ | o@ |
| Ç | o_ |
| È | XYZ{X |
| É | -1 |
| Ê | l |
| Ë | mDEF{D |
| Ì | gJ |
| Í | n2 |
| Î | g |
| Ï | XYZ{Y |
| Ð | $new Date($ |
| Ñ | *2 |
| Ò | -~ |
| Ó | ~- |
| Ô | w |
| Õ | y |
| × | r*1 |
Code: (33 bytes in ISO-8859-1)
Input:
JS code:
Output: