Add content on to the beginning of something (usually a file).
Questions tagged [prepend]
497 questions
765
votes
10 answers
Append integer to beginning of list in Python
How do I prepend an integer to the beginning of a list?
[1, 2, 3] ⟶ [42, 1, 2, 3]
gen
- 9,528
- 14
- 35
- 64
750
votes
8 answers
How do I prepend to a short python list?
list.append() appends to the end of a list. This explains that list.prepend() does not exist due to performance concerns for large lists. For a short list, how do I prepend a value?
hurrymaplelad
- 26,645
- 10
- 56
- 76
356
votes
11 answers
Most efficient way to prepend a value to an array
Assuming I have an array that has a size of N (where N > 0), is there a more efficient way of prepending to the array that would not require O(N + 1) steps?
In code, essentially, what I currently am doing is
function prependArray(value, oldArray) {
…
samccone
- 10,746
- 7
- 43
- 50
231
votes
9 answers
.append(), prepend(), .after() and .before()
I am pretty proficient with coding, but now and then I come across code that seems to do basically the same thing. My main question here is, why would you use .append() rather then .after() or vice verses?
I have been looking and cannot seem to…
Epik
- 3,327
- 4
- 17
- 23
196
votes
21 answers
Unix command to prepend text to a file
Is there a Unix command to prepend some string data to a text file?
Something like:
prepend "to be prepended" text.txt
One Two Three
- 22,327
- 24
- 73
- 114
160
votes
13 answers
How can I implement prepend and append with regular JavaScript?
How can I implement prepend and append with regular JavaScript without using jQuery?
Ben
- 25,389
- 34
- 109
- 165
125
votes
6 answers
Adding code to a javascript function programmatically
I'm attempting to customize an existing JS library without modifying the original JS code. This code loads in a few external JS files which I do have access to, and what I'd like to do is change one of the functions contained in the original file…
Munzilla
- 3,805
- 5
- 31
- 35
119
votes
8 answers
How to insert element as a first child?
I want to add a div as a first element using jquery on each click of a button
91
votes
14 answers
Prepend a line to an existing file in Python
I need to add a single line to the first line of a text file and it looks like the only options available to me are more lines of code than I would expect from python. Something like this:
f = open('filename','r')
temp = f.read()
f.close()
f =…
Nick
- 9,792
- 7
- 50
- 60
90
votes
5 answers
Prepend std::string
What is the most efficient way to prepend std::string? Is it worth writing out an entire function to do so, or would it take only 1 - 2 lines? I'm not seeing anything related to an std::string::push_front.
zeboidlund
- 9,731
- 31
- 118
- 180
82
votes
4 answers
How to prepend int to slice
I have a slice which I created using
var x []int;
for i := 2; i < 10; i += 2 {
x = append(x, i);
}
I want to prepend an integer to this slice, something like
x = append(2, x)
but obviously it won't work since append needs a slice as the first…
coda
- 2,188
- 2
- 22
- 26
82
votes
2 answers
D3.js prepend (similar to jQuery prepend)
I like the usage of append in D3, and I'm looking for prepend.
Does this exist in D3?
Mia
- 6,220
- 12
- 47
- 81
61
votes
5 answers
What is the idiomatic way to prepend to a vector in Clojure?
Prepending to a list is easy:
user=> (conj '(:bar :baz) :foo)
(:foo :bar :baz)
Appending to a vector is easy:
user=> (conj [:bar :baz] :foo)
[:bar :baz :foo]
How do I (idiomatically) prepend to a vector, while getting back a vector?
This does not…
0x89
- 2,940
- 2
- 31
- 30
53
votes
2 answers
What's the difference between `::` and `+:` for prepending to a list)?
List has 2 methods that are specified to prepend an element to an (immutable) list:
+: (implementing Seq.+:), and
:: (defined only in List)
+: technically has a more general type signature—
def +:[B >: A, That](elem: B)(implicit bf:…
Mechanical snail
- 29,755
- 14
- 88
- 113
49
votes
7 answers
jquery - keep window from changing scroll position while prepending items to a list?
I have a page that displays messages and I want it to work just like Facebook, but without the lazy loader. Messages are displayed in chronological order, most recent last.
My message list is initially populated x number of most recent messages, and…
Redtopia
- 4,947
- 7
- 45
- 68