| def mapReduce = { collection, mapper, reducer -> | |
| collection.groupBy(mapper) | |
| .collectEntries { k, v -> | |
| [k, reducer(v)] | |
| } | |
| } | |
| mapReduce([1, 6, 3, 7, 3, 9, 1, 2, 10, 9, 5, 8, 4], | |
| { it % 2 ? "odd" : "even" }, | |
| { it.size }) |
| var TextEncoder = require("text-encoding").TextEncoder; | |
| var TextDecoder = require("text-encoding").TextDecoder; | |
| var jsSource = ""; | |
| process.stdin.resume(); | |
| process.stdin.on("data", function(buf) { | |
| jsSource += buf.toString(); | |
| }); | |
| process.stdin.on("end", function() { |
| <!DOCTYPE html> | |
| <html lang="en"> | |
| <head> | |
| <meta charset="UTF-8"> | |
| <meta name="viewport" content="width=device-width, initial-scale=1.0"> | |
| <title>Jordan Curve Inscribed Lines</title> | |
| <style> | |
| body { font-family: monospace; } | |
| .canvas-section { display: inline-block; } | |
| canvas { border: 1px solid black; } |
JavaScript is a multi-paradigm language, supporting imperative, object-oriented, and functional styles. This presentation is intended to add some tools to your toolbelt. With familiarity of its patterns, functional JS can be very expressive. These patterns often follow from JS best practices:
Array.prototype or Object.prototype with nonstandard functionality; use utility functions
| #!/bin/sh | |
| set -ex | |
| mkdir -p /opt/jdk | |
| tar zxvf jdk.tar.gz -C /opt/jdk --strip-components=1 | |
| rm jdk.tar.gz | |
| rm /opt/jdk/lib/src.zip | |
| /opt/jdk/bin/jlink \ | |
| --module-path /opt/jdk/jmods \ |
| for d in ./*/ ; do (cd "$d" && git log --author="<name here>" --pretty=tformat: --numstat | awk '{ add += $1; subs += $2; loc += $1 + $2 } END { printf "added lines: %s, removed lines: %s, total lines: %s\n", add, subs, loc }' -); done |
| // error[E0502]: cannot borrow `window` as mutable because it is also borrowed as immutable | |
| // --> src/main.rs:14:9 | |
| // | | |
| // 14 | window.poll(|event| { | |
| // | ^ ---- ------- immutable borrow occurs here | |
| // | | | | |
| // | _________| immutable borrow used by call, in later iteration of loop | |
| // | | | |
| // 15 | | match event { | |
| // 16 | | WindowEvent::Close => { |
| /* In this game, alice and bob take turns removing any vertex of nonzero even | |
| * degree from an undirected graph, which also removes all connected edges. | |
| * The winner is the last player able to do so. | |
| */ | |
| //compactify vertex indices to improve memoization cache hit rates | |
| function simplify(edges) { | |
| const mappings = edges | |
| .flat() | |
| .reduce((uniq, v) => uniq.includes(v) ? uniq : [...uniq, v], []) |
| static String trimBytes(String input, int lengthBytes, Charset charset) { | |
| if (input == null) return null | |
| if (input.getBytes(charset).length <= lengthBytes) return input | |
| def bytes = charset.encode(input) | |
| bytes.limit(Math.min(lengthBytes, bytes.limit())) | |
| def chars = charset.newDecoder() | |
| .onMalformedInput(CodingErrorAction.IGNORE) | |
| .onUnmappableCharacter(CodingErrorAction.IGNORE) | |
| .decode(bytes) |
| const R = require("ramda"); | |
| //state operations | |
| const updStack = R.curry((prop, updater, state) => R.over(R.lensProp(prop), updater, state)); | |
| const updCall = (stackOp) => updStack("callStack", stackOp); | |
| const updData = (stackOp) => updStack("dataStack", stackOp); | |
| //stack operations | |
| const pop = R.curry((num, stack) => { | |
| if (stack.length < num) throw new Error("Stack underflow!"); |