ERB(1) Ruby Programmers Reference Guide ERB(1)
erb — Ruby Templating
erb [–version] [-UPdnvx] [-E ext[:int]] [-S level] [-T mode] [-r library] [–] [file …]
erb is a command line front-end for ERB library, which is an implementa‐
tion of eRuby.
ERB provides an easy to use but powerful templating system for Ruby.
Using ERB, actual Ruby code can be added to any plain text document for
the purposes of generating document information details and/or flow con‐
erb is a part of Ruby.
–version Prints the version of erb.
Specifies the default value(s) for external encodings and
internal encoding. Values should be separated with colon
You can omit the one for internal encodings, then the
value (Encoding.default_internal) will be nil.
-P Evaluates lines starting with % as Ruby code and removes
the tailing EOLs.
-S level Specifies the safe level in which eRuby script will run.
-T mode Specifies trim mode (default 0). mode can be one of
0 EOL remains after the embedded ruby script
1 EOL is removed if the line ends with %>.
2 EOL is removed if the line starts with <% and ends with %>.
– EOL is removed if the line ends with -%>.
And leading whitespaces are removed if the
erb directive starts with <%-. -U can be one of Sets the default value for internal encod‐ ings (Encoding.default_internal) to UTF-8. -d --debug Turns on debug mode. $DEBUG will be set to true. -h --help Prints a summary of the options. -n Used with -x. Prepends the line number to each line in the output. -v Enables verbose mode. $VERBOSE will be set to true. -x Converts the eRuby script into Ruby script and prints it without line numbers. EXAMPLES Here is an eRuby script
<% require 'prime' -%>
<%= __FILE__ %>
% erb -T – example.erb
And see ri documentation for ERB class.
Security vulnerabilities should be reported via an email to
⟨email@example.com⟩. Reported problems will be published after
And you can report other bugs and feature requests via the Ruby Issue
Tracking System (http://bugs.ruby-lang.org). Do not report security vul‐
nerabilities via the system because it publishes the vulnerabilities
Written by Masatoshi SEKI.
UNIX November 15, 2012 UNIX