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diff --git a/doc/talks/go_talk-20100112.html b/doc/talks/go_talk-20100112.html deleted file mode 100644 index 2e3643512..000000000 --- a/doc/talks/go_talk-20100112.html +++ /dev/null @@ -1,411 +0,0 @@ -<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" - "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> -<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> -<head> -<title>Go (January 12, 2010)</title> -<meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> -<meta name="font-size-adjustment" content="-1" /> -<link rel="stylesheet" href="slidy.css" - type="text/css" media="screen, projection, print" /> -<script src="slidy.js" type="text/javascript"> -</script> -</head> -<body> -<!-- this defines the slide background --> - -<div class="background"> - - <div class="header"> - <!-- sized and colored via CSS --> - </div> - - <div class="footer"></div> - </div> - -<div class="slide titlepage"> -<div style="height: 135px; width: 480px; overflow: hidden; position: fixed; top: auto; bottom: 10px; left: auto; right: 0; "> -<img src="../gordon/bumper480x270.png" style="margin: -135px 0 0 0;"/> -</div> -<!-- <img src="google.png" style="position: fixed; top: auto; bottom: 30px; left: 20px; right: auto;"/> --> -<br/> -<img src="../go-logo-white.png"> -<br/> -<br/> -<h1 style="padding-right: 0pt; margin-right: 0pt; color: #0066cc; font-size: 250%; border-bottom: 0px;">The Go Programming Language</h1> -<div style="color: #ffcc00;"> -<h2>Russ Cox</h2> -<!-- <h3><i>rsc@google.com</i></h3> --> -<br/> -<h3>Stanford University<br/><br/>January 12, 2010</h3> -</div> -</div> - -<div class="slide"> - <h1>Go</h1> - - <h2>New</h2> - <h2>Experimental</h2> - <h2>Concurrent</h2> - <h2>Garbage-collected</h2> - <h2>Systems</h2> - <h2>Language</h2> -</div> - -<div class="slide"> - <h1>Hello, world</h1> -<pre> -package main - -import "fmt" - -func main() { - fmt.Printf("Hello, 世界\n") -} -</pre> -</div> - -<div class="slide"> - <h1>History</h1> - - <h2>Design started in late 2007.</h2> - <h2>Implementation starting to work mid-2008.</h2> - <h2>Released as an open source project in November 2009.</h2> - <h2>Work continues.<h2> - <h2>Robert Griesemer, Ken Thompson, Rob Pike, Ian Lance Taylor, Russ Cox, many others</h2> -</div> - -<div class="slide"> - <h1>Why?</h1> - - <h2>Go fast!</h2> - <h2>Make programming fun again.</h2> -</div> - -<div class="slide"> - <h1>Why isn't programming fun?</h1> - - <div class="incremental"> - <h2>Compiled, statically-typed languages (C, C++, Java) require too much typing and too much typing:</h2> - - <ul> - <li>verbose, lots of repetition</li> - <li>too much focus on type hierarchy</li> - <li>types get in the way as much as they help</li> - <li>compiles take far too long</li> - </ul> - </div> - - <div class="incremental"> - <h2>Dynamic languages (Python, JavaScript) fix these problems (no more types, no more compiler) but introduce others:</h2> - - <ul> - <li>errors at run time that should be caught statically</li> - <li>no compilation means slow code</li> - </ul> - </div> - - <h2 class="incremental">Can we combine the best of both?</h2> -</div> - -<div class="slide"> - <h1>Go</h1> - - <h2>Make the language fast.</h2> - <h2>Make the tools fast.</h2> -</div> - -<div class="slide"> - <h1>Go Approach: Static Types</h1> - - <h2>Static types, but declarations can infer type from expression:</h2> - -<pre> -var one, hi = 1, "hello" - -var double = func(x int) int { return x*2 } -</pre> - - <h2>Not full Hindley-Milner type inference.</h2> -</div> - - -<div class="slide"> - <h1>Go Approach: Methods</h1> - - <h2>Methods can be defined on any type.</h2> - -<pre> -type Point struct { - X, Y float64 -} - -func (p Point) Abs() float64 { - return math.Sqrt(p.X*p.X + p.Y*p.Y) -} -</pre> -</div> - -<div class="slide"> - <h1>Go Approach: Methods</h1> - - <h2>Methods can be defined on any type.</h2> - -<pre> -type MyFloat float64 - -func (f MyFloat) Abs() float64 { - v := float64(f) - if v < 0 { - v = -v - } - return v -} -</pre> -</div> - -<div class="slide"> - <h1>Go Approach: Abstract Types</h1> - - <h2>An interface type lists a set of methods. Any value with those methods satisfies the interface.</h2> - -<pre> -type Abser interface { - Abs() float64 -} - -func AbsPrinter(a Abser) -</pre> - - <h2>Can use Point or MyFloat (or ...):</h2> - -<pre> -p := Point{3, 4} -AbsPrinter(p) - -f := MyFloat(-10) -AbsPrinter(f) -</pre> - - <h2>Notice that Point never declared that it implements Abser. It just does. Same with MyFloat.</h2> -</div> - -<div class="slide"> - <h1>Go Approach: Packages</h1> - - <h2>A Go program comprises one or more packages.</h2> - <h2>Each package is one or more source files compiled and imported as a unit.</h2> -<pre> -package draw - -type Point struct { - X, Y int -} -</pre> - -<pre> -package main - -import "draw" - -var p draw.Point -</pre> -</div> - -<div class="slide"> - <h1>Go Approach: Visibility</h1> - - <h2>Inside a package, all locally defined names are visible in all source files.</h2> - - <h2>When imported, only the upper case names are visible.</h2> - -<pre> -package draw - -type <span style="color: black;">Point</span> struct { - <span style="color: black;">X</span>, <span style="color: black;">Y</span> int - dist float64 -} - -type cache map[Point] float64 -</pre> - -<h2>Clients that <code>import "draw"</code> can use the black names only.</h2> - -<h2>“Shift is the new <code>public</code>.”</h2> -</div> - -<div class="slide"> - <h1>Go Approach: Concurrency</h1> - - <h2>Cheap to create a new flow of control (goroutine):</h2> - -<pre> -func main() { - go expensiveComputation(x, y, z) - anotherExpensiveComputation(a, b, c) -} -</pre> - - <h2>Two expensive computations in parallel.</h2> -</div> - -<div class="slide"> - <h1>Go Approach: Synchronization</h1> - - <h2>Use explicit messages to communicate and synchronize.</h2> - -<pre> -func computeAndSend(ch chan int, x, y, z int) { - ch <- expensiveComputation(x, y, z) -} - -func main() { - ch := make(chan int) - go computeAndSend(ch, x, y, z) - v2 := anotherExpensiveComputation(a, b, c) - v1 := <-ch - fmt.Println(v1, v2) -} -</pre> - <h2>Notice communication of result in addition to synchronization.</h2> -</div> - -<div class="slide"> - <h1>Go Fast: Language</h1> - - <h2 class="incremental">Static types: enough to compile well, but inferred much of the time.</h2> - - <h2 class="incremental">Methods: on any type, orthogonal to type system.</h2> - - <h2 class="incremental">Abstract types: interface values, relations inferred statically.</h2> - - <h2 class="incremental">Visibility: inferred from case of name.</h2> - - <h2 class="incremental">Concurrency: lightweight way to start new thread of control.</h2> - - <h2 class="incremental">Synchronization: explicit, easy message passing.</h2> - - <br/> - - <h2 class="incremental">Lightweight feel of a scripting language but compiled.</h2> -</div> - -<div class="slide"> - <h1>Compile fast</h1> - - <div class="incremental"> - <h2>Observation: much of the compile time for a source file is spent processing - other, often unrelated files.</h2> - - <h2>In C: <code>a.c</code> includes <code>b.h</code>, which includes <code>c.h</code>, which includes <code>d.h</code>. - </h2> - - <h2>Except that it's more often a tree instead of a chain.</h2> - - <h2>On my Mac (OS X 10.5.8, gcc 4.0.1):</h2> - <ul> - <li>C: <code>#include <stdio.h></code> reads 360 lines from 9 files. - <li>C++: <code>#include <iostream></code> reads 25,326 lines from 131 files. - <li>Objective C: <code>#include <Carbon/Carbon.h></code> reads 124,730 lines from 689 files. - </ul> - - <h2>And we haven't done any real work yet!</h2> - - <h2>Same story in Java, Python, but reading binaries instead of source files.</h2> - </div> -</div> - -<div class="slide"> - <h1>Implementation: Summarize Dependencies</h1> - -<pre> -package gui - -import "draw" - -type Mouse struct { - Loc draw.Point - Buttons uint -} -</pre> - <h2>Compiled form of <code>gui</code> summarizes the necessary part of <code>draw</code> (just <code>Point</code>).</h2> - -</div> - -<div class="slide"> - <h1>Implementation: Summarize Dependencies</h1> - - <h2>Compiled form of <code>gui</code> summarizes the necessary part of <code>draw</code> (just <code>Point</code>). Pseudo-object:</h2> - -<pre> -package gui -type draw.Point struct { - X, Y int -} -type gui.Mouse struct { - Loc draw.Point - Buttons uint -} -</pre> - - <h2>A file that imports <code>gui</code> compiles without consulting <code>draw</code> or its dependencies.</h2> - - <h2>In Go: <code>import "fmt"</code> reads <i>one</i> file: 184 lines summarizing types from 7 packages.</h2> - - <h2>Tiny effect in this program but can be exponential in large programs.</h2> -</div> - -<div class="slide"> - <h1>Compilation Demo</h1> - - <h2>Build all standard Go packages: ~120,000 lines of code.</h2> -</div> - -<div class="slide"> - <h1>Go Status</h1> - - <div class="incremental"> - <div> - <h2>Open source:</h2> - <ul> - <li>released on November 10, 2009 - <li>regular releases (~ weekly) - <li>all development done in public Mercurial repository - <li>outside contributions welcome - </ul> - </div> - - <div> - <h2>Portable:</h2> - <ul> - <li>FreeBSD, Linux, OS X (x86, x86-64) - <li>(in progress) Linux arm, Native Client x86, Windows x86. - </ul> - </div> - - <div> - <h2>Still in progress, experimental. Yet to come:</h2> - <ul> - <li>mature garbage collector - <li>generics? - <li>exceptions? - <li>unions or sum types? - </ul> - </div> - </div> - -</div> - -<div class="slide titlepage"> - <h1>Questions?</h1> - <br><br> - <center> - <img src="../gordon/bumper640x360.png"> - </center> - <br><br> - <div style="color: #ffcc00;"> - <!-- <h3><i>rsc@google.com</i></h3> --> - </div> -</div> - -</body></html> |