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How can I check whether a option already exist in select by JQuery
..."#your_select_id option[value=<enter_value_here>]").length == 0 ){
alert("option doesn't exist!");
}
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An efficient way to transpose a file in Bash
...ill help answer some of the questions below and generally clarify what the script is doing. It also uses tabs as the separator which the OP had originally asked for so it'd handle empty fields and it coincidentally pretties-up the output a bit for this particular case.
$ cat tst.awk
BEGIN { FS=OFS=...
Windows shell command to get the full path to the current directory?
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That does the wrong thing - finds the path of the batch script, not the current directory.
– Harry Johnston
Feb 9 '15 at 23:47
2
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RVM is not working in ZSH
...
Do you have this line in your ~/.zshrc?
[[ -s "$HOME/.rvm/scripts/rvm" ]] && . "$HOME/.rvm/scripts/rvm"
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What is the difference between String.slice and String.substring?
.... Too large values are truncated to the length of the string:
alert ( "testme" .substring (-2)); // "testme", -2 becomes 0
Furthermore, if start > end, the arguments are interchanged, i.e. plot line returns between the start and end:
alert ( "testme" .substring (4, -1)); // "test"
...
Formatting a number with exactly two decimals in JavaScript
...adays, you can use the Intl.NumberFormat constructor. It's part of the ECMAScript Internationalization API Specification (ECMA402). It has pretty good browser support, including even IE11, and it is fully supported in Node.js.
const formatter = new Intl.NumberFormat('en-US', {
minimumFraction...
How to initialize an array's length in JavaScript?
...}) gives you an array with length 5 and values 0,1,2,3,4.
Array(5).forEach(alert) does nothing, Array.apply(null, Array(5)).forEach(alert) gives you 5 alerts
ES6 gives us Array.from so now you can also use Array.from(Array(5)).forEach(alert)
If you want to initialize with a certain value, these are ...
What is better, curl or wget? [closed]
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I have never faced any problem shelling out WGET to Perl scripts to automate downloading stuff. However, with CURL, I frequently encounter error 18 - transfer closed with outstanding read data remaining (see stackoverflow.com/questions/1759956/…). This error I mostly get while tr...
Execute ssh with password authentication via windows command prompt
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What about this expect script?
#!/usr/bin/expect -f
spawn ssh root@myhost
expect -exact "root@myhost's password: "
send -- "mypassword\r"
interact
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Asynchronous Process inside a javascript for loop [duplicate]
...j = 10;
for (i = 0; i < j; i++) {
await asycronouseProcess();
alert(i);
}
Remember, this works only if asycronouseProcess is returning a Promise
If asycronouseProcess is not in your control then you can make it return a Promise by yourself like this
function asyncProcess() {
ret...