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Check if a method exists
Is there any way I can test if a method exists in Objective-C?
5 Answers
5
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How to exit in Node.js
...()
From the docs:
process.exit([exitcode])
Ends the process with the specified code. If omitted, exit uses the 'success' code 0.
To exit with a 'failure' code:
process.exit(1);
The shell that executed node should see the exit code as 1.
...
Oracle: If Table Exists
...n Oracle database, and was hoping Oracle had something similar to MySQL's IF EXISTS construct.
15 Answers
...
Where is Python's sys.path initialized from?
...al
location on the filesystem based on what the operating system tells
it. If the OS just says "python" is running, it finds itself in $PATH.
It resolves any symbolic links. Once it has done this, the path of
the executable that it finds is used as the value for sys.executable, no ifs,
ands, or buts...
What does the star operator mean, in a function call?
... to accept any number of positional and/or named arguments that aren't specifically named in the declaration.
Example:
def sum(*values):
s = 0
for v in values:
s = s + v
return s
s = sum(1, 2, 3, 4, 5)
or with **:
def get_a(**values):
return values['a']
s = get_a(a=1, ...
How do I check if a number evaluates to infinity?
...
if (result == Number.POSITIVE_INFINITY || result == Number.NEGATIVE_INFINITY)
{
// ...
}
You could possibly use the isFinite function instead, depending on how you want to treat NaN. isFinite returns false if your numbe...
Moving decimal places over in a double
...
If you use double or float, you should use rounding or expect to see some rounding errors. If you can't do this, use BigDecimal.
The problem you have is that 0.1 is not an exact representation, and by performing the calculat...
Focus Next Element In Tab Index
...r curIndex = currentElement.tabIndex; //get current elements tab index
if(curIndex == lastTabIndex) { //if we are on the last tabindex, go back to the beginning
curIndex = 0;
}
var tabbables = document.querySelectorAll(".tabable"); //get all tabable elements
for(var i=0; i<...
Retrieve column names from java.sql.ResultSet
...ame = rsmd.getColumnName(1);
and you can get the column name from there. If you do
select x as y from table
then rsmd.getColumnLabel() will get you the retrieved label name too.
share
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improve...
How to validate date with format “mm/dd/yyyy” in JavaScript?
...
function isValidDate(dateString)
{
// First check for the pattern
if(!/^\d{1,2}\/\d{1,2}\/\d{4}$/.test(dateString))
return false;
// Parse the date parts to integers
var parts = dateString.split("/");
var day = parseInt(parts[1], 10);
var month = parseInt(parts[0], ...