ok

oK oK is a toy interpreter for a dialect of the K programming language which aims to be an implementation of K5, the still-evolving bleeding edge version of the language. Expect oK to be buggy, incomplete and occasionally flat-out wrong, but slowly improving over time. Read the oK Manual for an overview of oK's operators and syntax. If you are interested in learning more about K, consider downloading the free version of kdb from Kx Systems, the fine makers of K. Alternatively, Kona is an open-source reimplementation of K3/K4. oK does not intend to be particularly fast or suitable for any practical purpose beyond learning, instead emphasizing simplicity of implementation. JavaScript was chosen as an implementation language because it is familar to many programmers and has first-class functions. Trying oK The easiest way to run oK is using the Browser-based REPL. This REPL features a few special commands which can be issued at the beginning of a line: \\ (while entering a multiline expression) cancel this expression. \e toggle the scratchpad editor pane. This editor's content is persisted via localstorage (in case your browser crashes or is closed accidentally). \r run the contents of the editor pane. Alternately, press shift+enter with the editor focused. \c clear the output log. \t time executing the remainder of the line. \f list all presently defined functions. \v list all presently defined variables. \u generates a code url from the remainder of the line, as described below. oK provides several numbered IO verbs: dyadic 0: takes a symbol or string as its left argument and writes the right argument to that destination as text. The right argument can be a symbol, a string, or a list of symbols or strings. In the browser-based REPL the symbol is ignored and output is always sent to the console. In the command-line REPL output is sent to a file as specified by the left argument, or to stdout if the left argument is empty. monadic 0: reads the content of a file or a URL. In the browser-based REPL it takes a string as its right argument and performs a synchronous HTTP request to that URL. The result will be a tuple containing the HTTP status code followed by the response, if any. You can use this in conjunction with pastebins to load code from elsewhere or access RESTful web APIs. Note that most web browsers restrict cross-site HTTP requests from javascript under the same-origin policy- you'll need a server which responds with an Access-Control-Allow-Origin header. GitHub gists will do: url: "https://gist.githubusercontent.com/anonymous/cc0ef05c00940044eb0a/raw/" "https://gist.githubusercontent.com/anonymous/cc0ef05c00940044eb0a/raw/" 0:url (200 "/ generate a times table\nt*/:t:!10\n") .*|0:url (0 0 0 0 0 0 0 0 0 0 0 1 2 3 4 5 6 7 8 9 0 2 4 6 8 10 12 14 16 18 0 3 6 9 12 15 18 21 24 27 0 4 8 12 16 20 24 28 32 36 0 5 10 15 20 25 30 35 40 45 0 6 12 18 24 30 36 42 48 54 0 7 14 21 28 35 42 49 56 63 0 8 16 24 32 40 48 56 64 72 0 9 18 27 36 45 54 63 72 81) In the command-line REPL 0: reads a file as text. The right argument can be a symbol or a string specifying the file path. If the path is to a directory, 0: returns its listing. If the path is empty and oK is not running interactively, 0: tries to read text from stdin until it encounters a '\n'. monadic 1: works just like monadic 0: except it expects the response to be JSON rather than arbitrary text, and it attempts to parse it into a K data structure you can then manipulate: url:"http://api.openweathermap.org/data/2.5/weather?q=London,uk" "http://api.openweathermap.org/data/2.5/weather?q=London,uk" t:1:url (200;[coord:[lon:-0.13;lat:51.51];sys:[type:1;id:5091;message:0.0224;country:"GB";sunrise:1425709902;sunset:1425750674];weather:,[id:800;main:"Clear";description:"Sky is Clear";icon:"01d"];base:"cmc stations";main:[temp:288.11;pressure:1024;humidity:44;temp_min:286.85;temp_max:289.82];wind:[speed:6.2;deg:230];clouds:[all:0];dt:1425736003;id:2643743;name:"London";cod:200]) t[1;`weather;0;`description] "Sky is Clear" monadic 5: returns a printable string representation of the right argument, as in K3. Sometimes this can be useful for debugging: 5: 1 2 3 "1 2 3" 5:"foo" "\"foo\"" 5: {x+2*y} "{[x;y]x+2*y}" If you visit the page with a ?run= URL parameter, the remainder of the URL will be URI decoded and executed. The \u command can create a link for you based on an expression. You can combine this feature with monadic 0: to run larger programs: \u 1+2 oK code url: http://johnearnest.github.io/ok/index.html?run=%201%2B2 \u .*|0:"https://gist.githubusercontent.com/anonymous/cc0ef05c00940044eb0a/raw/" oK code url: http://johnearnest.github.io/ok/index.html?run=%20.*%7C0%3A%22https%3A%2F%2Fgist.githubusercontent.com%2Fanonymous%2Fcc0ef05c00940044eb0a%2Fraw%2F%22 Command Line Mode Alternatively, you can run oK via the command line with Node.js. test.js runs a series of automated tests: je@indigo$ node test.js You can also try out oK from the included REPL. Note that at the time of writing, the release version of Node.js does not portably support blocking reads from stdin- the REPL has been tested with Node v0.11.14 on OSX. je@indigo$ node repl.js oK v0.1 +/4 5 6 15 1 2 3+2 5 length error. a:"some text" "some text" "t"=a 0 0 0 0 0 1 0 0 1 This REPL is very simplistic compared to the CLI provided in a complete K interpreter and lacks interactive debugging facilities. When you're done, type \\ or press Ctrl+D to exit. If you supply a filename as an argument to the REPL, it will instead execute that file: je@indigo$ node repl.js examples/hangman.k _____ > p _pp__ > e _pp_e > a app_e > l apple Mobile On mobile devices like cell phones, try oK Mobile! Tilting your device horizontally will provide a QWERTY touch-keyboard, and a vertical orientation will provide a calculator-like keypad which provides access to all K verbs and adverbs