ERB

Introduction

ERB stands for Embedded Ruby, and is used to insert Ruby variables inside templates, e.g. HTML and YAML. ERB is a Ruby class that accepts text, and evaluates and replaces Ruby code surrounded by ERB markup.

Syntax

<% number = rand(10) %> this code will be evaluated
<%= number %> this code will be evaluated and inserted into the output
<%# comment text %> this comment will not be evaluated

Remarks

Conventions:

ERB as a template: Abstract business logic into accompanied helper code, and keep your ERB templates clean and readable for people without Ruby knowledge.
Append files with .erb: e.g. .js.erb, .html.erb, .css.erb, etc.

Found a mistake? Have a question or improvement idea? Let me know.

ERB:

* ERB

* Parsing ERB

Table Of Contents

0 Getting started

1 Casting type conversions

2 Arrays

3 Classes

4 Hashes

5 Blocks and procs and lambdas

6 Inheritance

7 Control flow

8 Strings

9 Symbols

10 Exceptions

11 Thread

12 Methods

13 Method missing

14 Numbers

15 Iteration

16 Regular Expressions and regex based operations

17 Comparable

18 Gem usage

19 Design patterns and idioms

20 Loading source files

21 Range

22 Comments

23 Operators

24 Operators

25 Special constants in Ruby

26 Modules

27 Ruby version manager

28 Gem creation / management

29 Constants

30 Variable scope and visibility

31 rbenv

32 Environment variables

33 Singletons

34 File I/O

35 Time

36 Queue

37 Destructuring

38 IRB

39 Enumerators

40 C extensions

41 Struct

42 Metaprogramming

43 Dynamic evaluation

44 instance eval

45 Message passing

46 Keyword arguments

47 DateTime

48 Truthiness

49 JSON with Ruby

50 Implicit receives, understanding

51 Monkey patching

52 Introspection

53 Monkey patching

54 Refinements

55 Monkey patching in Ruby

56 Catching exceptions with begin rescue

57 Command line apps

58 Debugging

59 Pure RSpec JSON API testing

60 Recursion

61 Installation

62 ERB

63 Introspection

64 Random numbers

65 Getting started with Hanami

66 OptionParser

67 Splat operator

68 Multidimensional Arrays

69 Enumerable

70 Ruby access modifiers

71 Operating system or shell commands

72 Contributors