book

Introducing Erlang, 2nd Edition

by Simon St. Laurent

March 2017

Beginner

212 pages

4h 47m

English

O'Reilly Media, Inc.

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Who This Book Is ForWho This Book Is Not ForWhat This Book Will Do For YouHow This Book WorksEtudes for ErlangWhy I Wrote This BookOther ResourcesAre You Sure You Want Erlang?Erlang Will Change YouConventions Used in This BookA Note on Erlang SyntaxUsing Code ExamplesHelp This Book GrowPlease Use It For GoodO’Reilly SafariHow to Contact UsAcknowledgments
InstallationFiring It UpFirst Steps: The ShellMoving through TextMoving through HistoryMoving through FilesDoing SomethingCalling FunctionsNumbers in ErlangWorking with Variables in the ShellSeeing Your Bound VariablesClearing Bound Variables in the Shell
Fun with funDefining ModulesFrom Module to funFunctions and Variable ScopeModule DirectivesDocumenting CodeDocumenting ModulesDocumenting FunctionsDocumenting Your Application
AtomsPattern Matching with AtomsAtomic BooleansGuardsUnderscoring That You Don’t CareAdding Structure: TuplesPattern Matching with TuplesProcessing Tuples
Logic Inside of FunctionsEvaluating CasesIf This, Then ThatVariable Assignment in case and if ConstructsThe Gentlest Side Effect: io:formatSimple RecursionCounting DownCounting UpRecursing with Return Values
StringsAsking Users for InformationGathering TermsGathering CharactersReading Lines of Text
List BasicsSplitting Lists into Heads and TailsProcessing List ContentCreating Lists with Heads and TailsMixing Lists and TuplesBuilding a List of Lists
Simple Higher-Order FunctionsCreating New Lists with Higher-Order FunctionsReporting on a ListRunning List Values Through a FunctionFiltering List ValuesBeyond List ComprehensionsTesting ListsSplitting ListsFolding Lists
The Shell Is a ProcessSpawning Processes from ModulesLightweight ProcessesRegistering a ProcessWhen Processes BreakProcesses Talking Amongst ThemselvesWatching Your ProcessesBreaking Things and Linking Processes
Flavors of ErrorsCatching Runtime Errors as They HappenRaising Exceptions with throwLogging Progress and FailureDebugging through a GUITracing MessagesWatching Function Calls

Mapping Your DataFrom Tuples to RecordsSetting Up RecordsCreating and Reading RecordsUsing Records in Functions and ModulesStoring Records in Erlang Term StorageCreating and Populating a TableSimple QueriesA Key Feature: Overwriting ValuesETS Tables and ProcessesNext StepsStoring Records in MnesiaStarting up MnesiaCreating TablesReading DataQuery List Comprehensions
The Origins of OTPCreating Services with gen_serverA Simple SupervisorPackaging an Application
Moving Beyond the Erlang ShellDistributed ComputingProcessing Binary DataInput and OutputTesting, Analyzing, and RefactoringNetworking and the WebData StorageExtending ErlangLanguages Built on ErlangCommunitySharing the Gospel of Erlang
Shell CommandsReserved WordsOperatorsGuard ComponentsCommon FunctionsStrings and FormattingData Types for Documentation and Analysis

Content preview from Introducing Erlang, 2nd Edition

Chapter 12. Next Steps Through Erlang

Hopefully you now feel comfortable writing basic Erlang programs, and understand roughly how modules and processes build into programs. You should be ready to experiment with writing Erlang code, but more importantly, you should be ready to explore other resources for mastering Erlang and its many powerful libraries. There’s a lot to explore!

Moving Beyond the Erlang Shell

The Erlang shell is a great place to test code and to poke and prod Erlang code. You’ll likely spend a lot more time in the shell if you keep using Erlang, but the way you use it may change.

You can compile and run Erlang code outside of the shell, which makes it much easier to integrate Erlang work with tools you typically use to manage code and related resources. Erlang’s make module is a common place to start, letting you create Emakefile files that provide instruction to the erl -make command. The escript command, described at http://erlang.org/doc/man/escript.html, will let you run Erlang from the command line in a variety of different environments.

If you want to automate your Erlang builds further, you may want to explore rebar3. You can mix rebar3 with other tools to apply the strengths of each.

If you want to use Erlang from an IDE, you may want to explore http://erlide.org/, a set of tools for working with Erlang in Eclipse. Emacs users will want to explore the Erlang mode.