Can anyone explain the below code please - asp.net-mvc-2

`where client.name.ToLower().Contains(name.ToLower())

Now it's clearer. It's a (badly done) case insensitive search for the name in the client.name. True if name is contained in client.name. Badly done because using international letters (clearly "international letters" don't exist. I mean letters from a culture different from you own. The classical example is the Turkish culture. Read this: http://www.i18nguy.com/unicode/turkish-i18n.html , the part titled Turkish Has An Important Difference), you can break it. The "right" way to do it is: client.name.IndexOf(name, StringComparison.CurrentCultureIgnoreCase) != -1. Instead of StringComparison.CurrentCultureIgnoreCase you can use StringComparison.InvariantCultureIgnoreCase. If you have to use tricks like the ToLower, it has been suggested that it's better to ToUpper both sides of the comparison (but it's MUCH better to use StringComparison.*)

Looks like LINQ to me.
I'm not really up-to-date on .NET these days, but I'd read that as looking for client objects whose name property is a case-insensitive match with the ToString property of the client variable, while allowing additional characters before or after, much like WHERE foo is like '%:some_value%' in SQL. If I'm right, btw, client is a terrible variable name in this instance.

This is a strange piece of code. It would be good to know a bit more about the client object. Essentially it is checking if the case insensitive name value on the client object contains the case insensitive value of the client object (as a string). So if the client name contains the string name of the class itself essentially.

.ToLower() returns the same string you call it on in all lowercase letters. Basically, this statement returns true if name.ToLower() is embedded anywhere within client.name.ToLower().
//If:<br/>
client.name = "nick, bob, jason";
name = "nick";
//Then:<br/>
client.name.ToLower().Contains(name.ToLower());
//would return true

Related

What's the correct way to convert from StringBuilder to String?

From what I've seen online, people seem to suggest that the toString() method is to be used, however the documentation states:
Creates a String representation of this object. The default representation is platform dependent. On the java platform it is the concatenation of the class name, "#", and the object's hashcode in hexadecimal.
So it seems like using this method might cause some problems down the line?
There is also mkString and result(). The latter of which seems to make the most sense. But I'm not sure what the differences between these 3 methods are and if that's how result() is supposed to be used.
The toString implementation currently just redirects to the result method anyway, so those two methods will behave in the same way. However, they express slightly different intent:
toString requests a textual representation of StringBuilders current state that is "concise but informative (and) that is easy for a person to read". So, theoretically, the (vague) specification of this method does not forbid abbreviating the result, or enhancing conciseness and readability in any other way.
result requests the actual constructed string. No different readings seem possible here.
Therefore, if you want to obtain the resulting string, use result to express your intent as clearly as possible.
In this way, the reader of your code won't have to wonder whether StringBuilder.toString might shorten something for the sake of "conciseness" when the string gets over 9000 kB long, or something like that.
The mkString is for something else entirely, it's mostly used for interspersing separators, as in "hello".mkString(",") == "h,e,l,l,o".
Some further links:
The paragraph with "hashcode in hexadecimal" describes the default. It is just documentation inherited from AnyRef, because the creator of StringBuilder didn't bother to provide more detailed documentation.
If you look into code, you'll see that toString is actually just delegating to result.
The documentation of StringBuilder also mentions result() in the introductory overview paragraph.
Just use result().
TL;DR; use result as stated in the docs.
toString MUST never be called in anything at all for another purpose other than a quick debug.
mkString is inherited from collections hierarchy and it will basically create another StringBuilder so is very inefficient.

How to get second #entitie.literal when I have two or more "same" entitity on same phrase

For example, my input text are:
You can I talk with someone
on entity I have:
#pron:aboutme = I, Me
#pron:aboutother = someone, anyone, everyone, Richard
So... I want get #pron:aboutother literal
The problem is #pron.literal returns "I" and not "someone"
How can get #pron:aboutother input literal for this case?
#sys-number is a shorthand syntax. In this case, you need to use full syntax <?entities['pron'].get(1).literal?> to get the literal of the second detected entity. It might be good to check if there are two entities of the type detected in the input before (otherwise you get arrayoutofbounds exception).

Subresource and path variable conflicts in REST?

Is it considered bad practice to design a REST API that may have an ambiguity in the path resolution? For example:
GET /animals/{id} // Returns the animal with the given ID
GET /animals/dogs // Returns all animals of type dog
Ok, that's contrived, because you would actually just do GET /dogs, but hopefully it illustrates what I mean. From a path resolution standpoint, it seems like you wouldn't know whether you were looking for an animal with id="dogs" or just all the dogs
Specifically, I'm interested in whether Jersey would have any trouble resolving this. What if you knew the id to be an integer?
"Specifically, I'm interested in whether Jersey would have any trouble resolving this"
No this would not be a problem. If you look at the JAX-RS spec § 3.7.2, you'll see the algorithm for matching requests to resource methods.
[E is the set of matching methods]...
Sort E using the number of literal characters in each member as the primary key (descending order), the number of capturing groups as a secondary key (descending order) and the number of capturing groups with non-default regular expressions (i.e. not ‘([^ /]+?)’) as the tertiary key (descending order)
So basically it's saying that the number of literal characters is the primary key of which to sort by (note that it is short circuiting; you win the primary, you win). So for example if a request goes to /animals/cat, #Path("/animals/dogs") would obviously not be in the set, so we don't need to worry about it. But if the request is to /animals/dogs, then both methods would be in the set. The set is then sorted by the number of literal characters. Since #Path("/animals/dogs") has more literal characters than #Path("/animals/"), the former wins. The capturing group {id} doesn't count towards literal characters.
"What if you knew the id to be an integer?"
The capture group allows for regex. So you can use #Path("/animals/{id: \\d+}"). Anything not numbers will not pass and lead to a 404, unless of course it is /animals/dogs.

RESTful query string convention for "value is present"

Say we have a URL like:
http://example.org/resources/?property=1
This will return every resource where the value of property is 1, pretty straightforward. But what if property is nullable, and we want to search for all resources with a non-null query string? I can think of a couple of ideas:
http://example.org/resources/?property
http://example.org/resources/?property=present
But the first one requires treating "" as a special value (and distinguishing it from http://example.org/resources/, where property isn't even in the URL -- which isn't necessarily straightforward in some frameworks), and the second requires declaring and documenting that present is a special value, which goes against the general principle that good API URLs ought to be obvious and unsurprising. And what if property is a free-text field that can't have any reserved words? Is there a well-accepted way of doing this?

Cool class and method names wrapped in ``: class `This is a cool class` {}?

I just found some scala code which has a strange class name:
class `This is a cool class` {}
and method name:
def `cool method` = {}
We can use a sentence for a class or method name!
It's very cool and useful for unit-testing:
class UserTest {
def `user can be saved to db` {
// testing
}
}
But why we can do this? How to understand it?
This feature exists for the sake of interoperability. If Scala has a reserved word (with, for example), then you can still refer to code from other languages which use it as a method or variable or whatever, by using backticks.
Since there was no reason to forbid nearly arbitrary strings, you can use nearly arbitrary strings.
As #Rex Kerr answered, this feature is for interoperablility. For example,
To call a java method,
Thread.yield()
you need to write
Thread.`yield`()
since yield is a keyword in scala.
The Scala Language Specification:
There are three ways to form an identifier. First, an identifier can
start with a letter which can be followed by an arbitrary sequence of
letters and digits. This may be followed by underscore ‘_’ characters
and another string composed of either letters and digits or of
operator characters. Second, an identifier can start with an operator
character followed by an arbitrary sequence of operator characters.
The preceding two forms are called plain identifiers. Finally, an
identifier may also be formed by an arbitrary string between
back-quotes (host systems may impose some restrictions on which
strings are legal for identifiers). The identifier then is composed of
all characters excluding the backquotes themselves.
Strings wrapped in ` are valid identifiers in Scala, not only to class names and methods but to functions and variables, too.
To me it is just that the parser and the compiler were built in a way that enables that, so the Scala team implemented it.
I think that it can be cool for a coder to be able to give real names to functions instead of getThisIncredibleItem or get_this_other_item.
Thanks for your questions which learnt me something new in Scala!