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When to use std::begin and std::end instead of container specific versions [duplicate]
Are there any general preferences or rules that explain when container specific versions of begin and end should be used instead of free functions std::begin and std::end ?
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What would be C++ limitations compared C language? [closed]
...nt question which asks about a generics library for C - the questioner specifically states that they do not want to use C++.
C is a complete programming language. C is not an arbitrary subset of C++. C is not a subset of C++ at all.
This is valid C:
foo_t* foo = malloc ( sizeof(foo_t) );
To m...
Preventing Laravel adding multiple records to a pivot table
... of an existing record by writing a very simple condition like this one :
if (! $cart->items->contains($newItem->id)) {
$cart->items()->save($newItem);
}
Or/and you can add unicity condition in your database, it would throw an exception during an attempt of saving a doublet.
Y...
What linux shell command returns a part of a string? [duplicate]
...
If you are looking for a shell utility to do something like that, you can use the cut command.
To take your example, try:
echo "abcdefg" | cut -c3-5
which yields
cde
Where -cN-M tells the cut command to return columns ...
How do I remove a single file from the staging area (undo git add)?
...
If I understand the question correctly, you simply want to "undo" the git add that was done for that file.
If you need to remove a single file from the staging area, use
git reset HEAD -- <file>
If you need to remove...
Convert a Unicode string to a string in Python (containing extra symbols)
...oblem of not being able to save unicode to a file sounds like an entirely different issue worthy of a separate question
– Mark Roddy
Jul 30 '09 at 16:03
5
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MySQL dump by query
...able" -u myuser -pxxxxxxxxx mydatabase
you can redirect it out to a file if you want :
mysql -e "select * from myTable" -u myuser -pxxxxxxxx mydatabase > mydumpfile.txt
Update:
Original post asked if he could dump from the database by query. What he asked and what he meant were different. H...
Access index of the parent ng-repeat from child ng-repeat
... and the issue was something else in my actual code. Still, I know it was difficult to find examples of this so I'm answering it in case someone else is looking.
<div ng-repeat="f in foos">
<div>
<div ng-repeat="b in foos.bars">
<a ng-click="addSomething($parent.$in...
How does Python's super() work with multiple inheritance?
...y are listed left to right. In this case, we are looking for __init__. So, if you define
class Third(First, Second):
...
Python will start by looking at First, and, if First doesn't have the attribute, then it will look at Second.
This situation becomes more complex when inheritance starts c...
How to use the 'main' parameter in package.json?
...is a module ID that is the primary entry point to your
program. That is, if your package is named foo, and a user installs
it, and then does require("foo"), then your main module's exports
object will be returned.
This should be a module ID relative to the root of your package
folder.
...