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How can I combine hashes in Perl?
... complex nested variables
Pitfalls
What do to when both hashes contain one or more duplicate keys
(see e.g., Perl - Merge hash containing duplicate keys)
(see e.g, Perl hashes: how to deal with duplicate keys and get possible pair)
Should a key-value pair with an empty value ever overwrite a ...
What does the “~” (tilde/squiggle/twiddle) CSS selector mean?
...edes (not necessarily immediately) the element represented by the
second one.
Consider the following example:
.a ~ .b {
background-color: powderblue;
}
<ul>
<li class="b">1st</li>
<li class="a">2nd</li>
<li>3rd</li>
<li class="b"...
Summarizing multiple columns with dplyr? [duplicate]
...it with the dplyr-syntax. I have a data frame with different variables and one grouping variable. Now I want to calculate the mean for each column within each group, using dplyr in R.
...
How do I force Postgres to use a particular index?
... Agreed, Forcing postgres to do it your way usually means you've done it wrong. 9/10 Times the planner will beat anything you can come up with. The other 1 time its because you made it wrong.
– Kent Fredric
Nov 21 '08 at 19:31
...
Android: alternate layout xml for landscape mode
How can I have one layout for landscape and one for portrait? I want to assume extra width and conserve vertical space when the user rotates the phone over sideways.
...
How can I trim leading and trailing white space?
...terstrip.white=TRUE.
If you want to clean strings afterwards you could use one of these functions:
# Returns string without leading white space
trim.leading <- function (x) sub("^\\s+", "", x)
# Returns string without trailing white space
trim.trailing <- function (x) sub("\\s+$", "", x)
# ...
How to enable file sharing for my app?
...
Is there any reason why it couldn't have effect in one application? I enabled it but the the App won't show up on iTunes File Sharing
– rraallvv
Feb 5 '13 at 7:40
...
How do function pointers in C work?
...dal, in this context it's interesting to explain that this is what enables one to write functionPtr = ******************addInt;
– Johannes Schaub - litb
May 10 '09 at 17:54
106
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Which iomanip manipulators are 'sticky'?
...king a basic_ostream and a built in numeric type.
22.2.6.2.2 [lib.locale.money.put.virtuals]: All do_put overloads for the money_put template.
27.6.2.5.4 [lib.ostream.inserters.character]: Overloads of operator<< taking a basic_ostream and one of the char type of the basic_ostream instantiat...
How to rename items in values() in Django?
...
Has anyone found a way to do this through tables (.values(supports__through_tables))?
– François Constant
Oct 2 '14 at 6:30
...