The following is code from an ERB tutorial. When I tried to execute the code, the compiler complained saying "(erb):16: undefined local variable or method `priority' for main:Object (NameError)". I cannot figure out the reason. Could someone please help me out?
require "erb"
# Create template.
template = %q{
From: James Edward Gray II <james#grayproductions.net>
To: <%= to %>
Subject: Addressing Needs
<%= to[/\w+/] %>:
Just wanted to send a quick note assuring that your needs are being
addressed.
I want you to know that my team will keep working on the issues,
especially:
<%# ignore numerous minor requests -- focus on priorities %>
% priorities.each do |priority|
* <%= priority %>
% end
Thanks for your patience.
James Edward Gray II
}.gsub(/^ /, '')
message = ERB.new(template, 0, "%<>")
# Set up template data.
to = "Community Spokesman <spokesman#ruby_community.org>"
priorities = [ "Run Ruby Quiz",
"Document Modules",
"Answer Questions on Ruby Talk" ]
# Produce result.
email = message.result
puts email
That ERB template looks mangled, a problem caused by your indentation. You just need to fix the middle:
<% priorities.each do |priority| %>
* <%= priority %>
<% end %>
The alternate syntax is to have a % at the very beginning of the line. In your case you have inadvertently added some spaces which are rendering that part of the ERB invalid.
Related
I'm a complete novice in Ruby and Nanoc, but a project has been put in my lap. Basically, the code for the page brings back individual URLs for each item linking them to the manual. I'm trying to create a URL that will list all of the manuals in one search. Any help is appreciated.
Here's the code:
<div>
<%
manuals = #items.find_all('/manuals/autos/*')
.select {|item| item[:tag] == 'suv' }
.sort_by {|item| item[:search] }
manuals.each_slice((manuals.size / 4.0).ceil).each do |manuals_column|
%>
<div>
<% manual_column.each do |manual| %>
<div>
<a href="<%= app_url "/SearchManual/\"#{manual[:search]}\"" %>">
<%= manual[:search] %>
</a>
</div>
<% end %>
</div>
<% end %>
</div>
As you didn't specify what items is returning, I did an general example:
require 'uri'
# let suppose that your items query has the follow output
manuals = ["Chevy", "GMC", "BMW"]
# build the url base
url = "www.mycars.com/search/?list_of_cars="
# build the parameter that will be passed by the url
manuals.each do |car|
url += car + ","
end
# remove the last added comma
url.slice!(-1)
your_new_url = URI::encode(url)
# www.mycars.com/?list_of_cars=Chevy,GMC,BMW
# In your controller, you will be able to get the parameter with
# URI::decode(params[:list_of_cars]) and it will be a string:
# "Chevy,GMC,BMW".split(',') method to get each value.
Some considerations:
I don't know if you are gonna use this on view or controller, if will be in view, than wrap the code with the <% %> syntax.
About the URL format, you can find more choices of how to build it in:
Passing array through URLs
When writing question on SO, please, put more work on that. You will help us find a quick answer to your question, and you, for wait less for an answer.
If you need something more specific, just ask and I can see if I can answer.
I'm trying to write a regular expression to replace <%= Name %> with "Some Person".
I'm using a regex because I want to modify it so that I don't have to worry about the spaces between = and Name as well as the E in Name and the %>
I tried:
body = %q(
Hello <%= Name %>,
This is a test. hello test
some more stuff here
and here.
<%= Name %>
)
parsed_body = body.gsub(/\A<%= Name %>\Z/, "Some person")
puts parsed_body
When parsed_body is printed out, the string is unchanged. What is wrong with my regex?
In your Regex, you have added the \A and \z anchors. These ensure that your regex only matches, if the string only contains exactly <%= Name %> with nothing before or after.
To match the your pattern anywhere in the string, you can simply remove the anchors:
parsed_body = body.gsub(/<%= Name %>/, "Some person")
Just another option considering what I am assuming you are trying to accomplish
tag_pattern = /(?<open_tag><%=\s*)(?<key>(\w+))(?<close_tag>\s*%>)/
body = <<-B
Hello,
My name is <%= Name %> and I know some things. Just because I am a
<%= Occupation %> doesn't mean I know everything, but I sure can
<%=Duty%> just as well as anyone else.
Also please don't replace <%= This %>
Thank you,
<%= Name %>
B
dict = {"Name" => "engineersmnky", "Occupation" => "Monkey", "Duty" => "drive a train"}
body.gsub(tag_pattern) {|m| dict[$2] || m }
#=> Hello,
# My name is engineersmnky and I know some things. Just because I am a
# Monkey doesn't mean I know everything, but I sure can
# drive a train just as well as anyone else.
# Also please don't replace <%= This %>
#
# Thank you,
# engineersmnky
In this case I used a dictionary of the anticipated portions of the "erb" to be replaced and used the block style of String#gsub to handle the replacements where $2 is the named capture key. When there is not a matching key it just leaves the match untouched e.g. "Also please don't replace <%= This %>"
You could implement this with any pattern you choose but if you are going to use "erb" style lines maybe try leveraging erb other wise the same will work below:
tag_pattern = (?<open_tag>{!!\s*)(?<key>(\w+))(?<close_tag>\s*!\?})
body = <<-B Hello,
My name is {!! Name !?} and I know some things. Just because I am a
{!! Occupation !?} doesn't mean I know everything, but I sure can
{!!Duty !?} just as well as anyone else.
Thank you,
{!! Name !?}
B
As long as you define tag_pattern correctly the replacement is fairly simple. Rubular Example
It looks like you're trying to write your own template parser, which is asking for a lot more trouble that it's worth considering those already exist.
However, this is the basic idea for such a thing:
erb = <<EOT
Owner: <%= name %>
Location: <%= address %>
EOT
FIELD_DATA = {
name: 'Olive Oyl',
address: '5 Sweethaven Village'
}
FIELD_RE = Regexp.union(FIELD_DATA.keys.map(&:to_s)).source # => "name|address"
puts erb.gsub(/<%=\s+(#{FIELD_RE})\s+%>/) { |k|
k # => "<%= name %>", "<%= address %>"
k[/\s+(\S+)\s+/, 1] # => "name", "address"
FIELD_DATA[k[/\s+(\S+)\s+/, 1].to_sym] # => "Olive Oyl", "5 Sweethaven Village"
}
Which, when run, outputs:
Owner: Olive Oyl
Location: 5 Sweethaven Village
This works because gsub can take a regular expression and a block. For every match of the expression it passes in the match to the block, which is then used to return the actual value being substituted in.
If you have a lot of target values, rather than use Regexp.union, instead use the RegexpTrie gem. See "Is there an efficient way to perform hundreds of text substitutions in Ruby?" for more information.
Again, template parsers exist, they've been around a long time, they're very well tested, and they handle edge cases you haven't thought about, so don't write a new partially-implemented one, instead reuse an existing one.
I have this function in my template:
<%= for {element, id} <- Enum.with_index(MyProject.PageView.Recursion.buildElements(#header_linkNumber),1) do %>
<%= render FabricaASA.ComponentView, #header_linkType,
button_id: "#{id}",
button_mainStyle: #header_mainStyle
%>
<% end %>
Now I would like to concatenate, on my right side, #header_mainStyle + id so that from other template, for each created element, I could pass: header_mainStyle1, header_mainStyle2,...header_mainStyleN
Also, on the left side, where I have button_mainStyle: I would like to concatenate #header_linkType + _mainStyle: so that I could dynamically change it to, link_mainStyle: or button_mainStyle:
Up to now I wasn't able to do it properly...
I'm afraid you are doing something wrong if you need such thing. Maybe there's a simpler solution...
Anyway: since some version of Phoenix (I'm sorry I don't know which one precisely, maybe 1.0?), #-variables are stored in #conn.assigns map and you can access them by name there. In older versions, these variables were macros and this kind of magic did not work.
So you can try to put this into the controller:
def index(conn, _params) do
render conn, "index.html", [var1: "var1"]
end
and this into the page template:
<p>var1: <%= #var1 %></p>
<p>assigns:</p>
<%= for i <- 1..10 do %>
<p>var<%= i %>:<p>
<pre><%=
varname = "var#{i}" |> String.to_atom
inspect(#conn.assigns[varname]) %>
</pre>
<% end %>
...you will see var1 to var10 bindings (screenshot: http://postimg.org/image/4b4790cjz/). But it's little bit black magic and probably wrong approach.
I am trying to create a loop only if index is defined. But it looks like
erb can't handle a loop within a if clause.
<% if(#index) %>
index <% index_files.each do |i| %> <%= i %> <% end %>;
<% end %>
Expected Result was:
index index.html index.php
or
""
Syntax error i got:
My flat approach failed as expected:
<% if(#index_files) %> try_files <% end %> <% index_files.each do |i| %> <%= i %> <% end %>
I defined index_files as undef => broke the each loop
I defined an empty array => since an empty array is defined it didn't work.
Maybe I can check the length of index_files?
Or do I need a complete different way to solve the problem?
I'm doing the same and it works for me, also for nginx ;).
For example:<% if #proxy_ignore_headers %> proxy_ignore_headers<% proxy_ignore_headers.each do |i| -%> <%= i %><% end -%>;
That works like a charm, the only difference with you is using () for the if condition, but I bet puppet supports (). It's weird, maybe you had pressed a bad combination generating a character that can't be seen but it's messing with your code, try writing all from scratch just in case.
You can see the full template here
Good luck
At first glance you just need to change
index_files.each
to
#index_files.each
The following view code generates a series of links with totals (as expected):
<% #jobs.group_by(&:employer_name).sort.each do |employer, jobs| %>
<%= link_to employer, jobs_path() %> <%= "(#{jobs.length})" %>
<% end %>
However, when I refactor the view's code and move the logic to a helper, the code doesn't work as expect.
view:
<%= employer_filter(#jobs_clone) %>
helper:
def employer_filter(jobs)
jobs.group_by(&:employer_name).sort.each do |employer,jobs|
link_to employer, jobs_path()
end
end
The following output is generated:
<Job:0x10342e628>#<Job:0x10342e588>#<Job:0x10342e2e0>Employer A#<Job:0x10342e1c8>Employer B#<Job:0x10342e0d8>Employer C#<Job:0x10342ded0>Employer D#
What am I not understanding? At first blush, the code seems to be equivalent.
In the first example, it is directly outputting to erb, in the second example it is returning the result of that method.
Try this:
def employer_filter(jobs)
employer_filter = ""
jobs.group_by(&:employer_name).sort.each do |employer,jobs|
employer_filter += link_to(employer, jobs_path())
end
employer_filter
end
Then call it like this in the view:
raw(employer_filter(jobs))
Also note the use of "raw". Once you move generation of a string out of the template you need to tell rails that you don't want it html escaped.
For extra credit, you could use the "inject" command instead of explicitly building the string, but I am lazy and wanted to give you what I know would work w/o testing.
This syntax worked as I hoped it would:
def employer_filter(jobs_clone)
jobs_clone.group_by(&:employer_name).sort.collect { |group,items|
link_to( group, jobs_path() ) + " (#{items.length})"
}.join(' | ').html_safe
end