So you think you wanna be a web developer...
Fork this, update your copy with answers.
They don't need to be precise - pseudo-code is fine in most cases.
Some questions don't have correct answers.
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SUBJECT: [dojo4-quiz] quiz-1
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https://gist.github.com/to-your-submission
==========================================================
- is this broken in html5? if so why? ==========================================================
<div id='teh_javascripts' />In HTML5, only "foreign" elements i.e. SVG act as self-closing tags when finished with '/>'. It has no effects on standard HTML tags and thus, when used with a 'div' tag, would still need a closing ''.
Sources:
- http://stackoverflow.com/questions/3558119/are-self-closing-tags-valid-in-html5
- http://dev.w3.org/html5/spec-author-view/syntax.html#syntax-start-tag
- http://dev.w3.org/html5/spec-author-view/syntax.html#foreign-elements
'http://domain.com:4242/foo/bar/baz.html'
Been a while... Not sure about the port.
GET /foo/bar/baz.html HTTP/1.1\r\n
Host: domain.com:4242\r\n
\r\n
Send that over the pipes and smoke it.
Source: http://en.wikipedia.org/wiki/Http
========================================================== 3. in any language you choose, write this to run in parallel
numbers = 20, 1
results = []
numbers.each do |number|
results.push( parallelize{ number * 2 } )
end
sum = reduce( results )
Wut.
========================================================== 4. in any language you choose, write this to run in parallel on multiple cores
numbers = 20, 1
results = []
numbers.each do |number|
results.push( parallelize{ number * 2 } )
end
sum = reduce( results )
Wut.
<label for='user.email'>
<input name='user.email'>Doesn't "for" reference the "id" of an element?
if @not_modified
render :status => status
endHopefully, 304
========================================================== 7. is this javascript broken? if so, why?
var submit = document.getElementById("submit");
submit.click();Is the intention to submit a form? HTML forms have a 'submit' event that can be triggered on them natively. If the script is supposed to account for previously bound click events on a submit button, it could be appropriate.
<!-- A -->
<table>
<tr>
<td class='key' style='width:33%'>
{{ dynamic_content_for(:key) }}
</td>
<td class='val'>
{{ dynamic_content_for(:val) }}
</td>
</tr>
</table>
<!-- B -->
<div class='fluid grid'>
<div class='row'>
<span class='key width33'>
{{ dynamic_content_for(:key) }}
</span>
<span class='val'>
{{ dynamic_content_for(:val) }}
</span>
</div>
</div>Doctrine states that HTML classes should be semantic. In that case, the width33 class is fairly useless. A better classname for that might be "skinny" or "small".
# A
if var == 42
"..."
end
# B
if 42 == var
"..."
endThe == operator can be overridden in Ruby. Since this might be much
more common on your own objects constructed for your app, you might be
expecting to use the overloaded == on whatever class the var
instance is. If the intention is to really check that var is most
certainly the Fixnum 42, place 42 first and hope that == wasn't
overriden there.
@response =
http_request(url, :method => method, :params => params, :headers => headers)
if @response.ok?
ship_it!
else
debugger!
endDon't depend on functioning external services. Build retries or graceful failures into the code. Expect 4XX & 5XX responses.
# A
if foo.bar.baz
'...'
end
# B
if foo
if foo.bar
if foo.bar.baz
'...'
end
end
endDepends how the code works. B is uglier, but provides nil safe checks
by using the nested if statements. A is cleaner given that you can
guarantee that your code won't blow up if intermediary calls raise
exceptions.
========================================================== 12. is this javascript broken? if so, why?
ajax(url)({
'method' : 'POST',
'params' : params,
'headers' : headers
});
It could be...
Assuming the ajax function, when passed a URL, returns another
function ready to be executed given an options object, it might work.
It may or may not provide functionality for callbacks. XMLHttpRequest objects act asynchronously natively in JS.
'#FFE'Guess: Gray Actual: Light Yellow (Manilla Folder)
0b101010Binary encoded: From right to left...
( 2**0 * 0 ) + ( 2**1 * 1 ) + ( 2**2 * 0 ) + ( 2**3 * 1 ) + ( 2**4 * 0 ) + ( 2**5 * 1 )
0 + 2 + 0 + 8 + 0 + 32
42
Should have known...
========================================================== 15. describe an algorithm to detect the 'edges' in these pixels
0 0 0 0 0 0 0 0 1 1 1 0 0 1 1 1 1 0 0 1 1 1 0 0 0 0 0 0 0 0
Start in the upper left corner. Loop through each cell per row, traversing from left to right, until an edge is found. Mark each edge cell that is encountered. Once the first edge is encountered, attempt to move in each direction to detect the next edge in the order of right, down, left, up. If an edge is detected, move the loop cursor to that cell and mark it. Ignore edges already detected. Once all edges have been detected for a group, continue looping from the last encountered edge.
$color = [@X, @R, @G, @B].as_hex
Opacity?
========================================================== 16. what are the advantages of static linking?
export HINT=$LD_RUN_PATH
From my understanding, static linking of dependencies provides a way to ensure that builds have fewer external requirements. In practice, this leads to a more seamless development experience as required packages/binaries/includes are always present. The trade offs might be around build complexity and size.
In the dynamic Ruby environment, I believe one can get closer to 'static linking' by vendoring gem sources in a project.
See @wycats' Tokkaido project for struggles with static vs. dynamic linking when building/compiling distributable Ruby binaries.
var uploader = new qq.FileUploader(options);
var image_ids = [];
uploader._uploadFileList = function(){
image_ids = [];
var args = Array.prototype.slice.call(arguments);
var result = qq.FileUploaderBasic.prototype._uploadFileList.apply(uploader, args);
return(result);
};
Ensuring:
- that the image_ids variable is reset when the
_uploadFileListfunction is called on theuploader - that the
_uploadFileListfunction from the basic uploader is used
jQuery('.help').find('a').attr('tabindex', '-1');
Guess: Places browser focus on the first link within the element that
has the .help class.
Actual: When a user hits the TAB key, links (<a>) within the .help
element are the first selected.
~ > run_api_tests_locally
"FAIL: you must access teh API from a box on EC2 with IP 1.2.3.4!"
A few options:
- Don't run the tests locally
- Run the tests locally against a locally hosted version of the API
- Separate all API logic from the network layer and run the tests against that assuming that the network layer simply provides an authenticated/authorized gateway into the API.
// A
User.prototype.first_name = function(){
return this.name.split(/\s+/)[0];
};
// B
User.prototype.first_name = function(){
return User.first_name_for(this.name);
};
User.first_name_for = function(name){
return name.split(/\s+/)[0];
};Subjective.
The first feels right for the 'object purists' in the house. Assume all Users need a name and that their first name can be derived from that.
The second feels better from a responsibility standpoint. An individual User instance does not need to know how to derive its own first name. But, the User 'class' knows that first names are typically derived by finding the first word of a person's name. This is a more functional approach that removes some state necessities.