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Find first element by predicate
...ily, exposing opportunities for optimization. For example, "find the first String with three consecutive vowels" need not examine all the input strings. Stream operations are divided into intermediate (Stream-producing) operations and terminal (value- or side-effect-producing) operations. Intermedia...
Git ignore file for Xcode projects
... (or none at all)
# This file is for SOURCE projects, where there are many extra
# files that we want to exclude
#
#########################
#####
# OS X temporary files that should never be committed
#
# c.f. http://www.westwind.com/reference/os-x/invisibles.html
.DS_Store
# c.f. http://www.west...
Is it good practice to NULL a pointer after deleting it?
...e aren't many deletes in your code to begin with, so the argument that the extra assignment causes clutter doesn't persuade me.
It's often convenient, when debugging, to see the null value rather than a stale pointer.
If this still bothers you, use a smart pointer or a reference instead.
I also se...
Forced naming of parameters in Python
...ed.
Cons:
Checking occurs during run-time, not compile-time.
Use of an extra parameter (though not argument) and an additional check. Small performance degradation respect to regular functions.
Functionality is a hack without direct support by the language (see note below).
When calling the fun...
Remove by _id in MongoDB console
...id field is not automatically generated (i.e. it is not an ObjectId, but a String), You can just write the value of the _id under quotation marks: db.your.database.remove({"_id": "your value"}).
– Aleksandar
Jun 4 '18 at 16:39
...
Using Rails serialize to save hash to database
...
The column type is wrong. You should use Text instead of String. Therefore, your migration should be:
def self.up
add_column :users, :multi_wrong, :text
end
Then Rails will properly convert it into YAML for you (and perform proper serialization). Strings fields are limited ...
How can I check whether a option already exist in select by JQuery
...w what "yourValue" is (for example, if it's user input). Building a single string just to let "jQuery do it" would require you to do input sanitization, and you end up with code practices that have haunted SQL for decades. So a -1 is completely unwarranted. The question even states that they want to...
How to install Android SDK Build Tools on the command line?
...dk --filter ...
The other answers don't mention that you can use constant string identifiers instead of indexes (which will change) for the filter options. This is helpful for unattended or scripted installs. Man for --filter option:
... This also accepts the identifiers returned by 'list sdk -...
How to check if field is null or empty in MySQL?
...ld1
from tablename
If you only want to check for null and not for empty strings then you can also use ifnull() or coalesce(field1, 'empty'). But that is not suitable for empty strings.
share
|
im...
Java regular expression OR operator
...
You can just use the pipe on its own:
"string1|string2"
for example:
String s = "string1, string2, string3";
System.out.println(s.replaceAll("string1|string2", "blah"));
Output:
blah, blah, string3
The main reason to use parentheses is to limit the scope o...