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How to check whether a file or directory exists?
...iven file or directory exists
func exists(path string) (bool, error) {
_, err := os.Stat(path)
if err == nil { return true, nil }
if os.IsNotExist(err) { return false, nil }
return false, err
}
Edited to add error handling.
...
How do I make a checkbox required on an ASP.NET form?
...ion for client side validation (using jQuery)...
function CheckBoxRequired_ClientValidate(sender, e)
{
e.IsValid = jQuery(".AcceptedAgreement input:checkbox").is(':checked');
}
code-behind for server side validation...
protected void CheckBoxRequired_ServerValidate(object sender, ServerValid...
Convert Python dictionary to JSON array
...
If you are fine with non-printable symbols in your json, then add ensure_ascii=False to dumps call.
>>> json.dumps(your_data, ensure_ascii=False)
If ensure_ascii is false, then the return value will be a
unicode instance subject to normal Python str to unicode
coercion rules in...
Mechanisms for tracking DB schema changes [closed]
...ed code to a production server) but we're still doing database updates manually. I would like to find or create a solution that allows us to work efficiently across servers with different environments while continuing to use Subversion as a backend through which code and DB updates are pushed aroun...
How do I get the information from a meta tag with JavaScript?
...
What you really want is 'let' to keep them locally defined ;)
– tommed
Mar 23 '15 at 21:54
26
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What is the equivalent of 'describe table' in SQL Server?
...u want, though unfortunately you have to query the views and join them manually.
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Annotating text on individual facet in ggplot2
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Typically you'd do something like this:
ann_text <- data.frame(mpg = 15,wt = 5,lab = "Text",
cyl = factor(8,levels = c("4","6","8")))
p + geom_text(data = ann_text,label = "Text")
It should work without specifying the factor variable comple...
split string only on first instance - java
... length will be no greater than n, and the array's last entry will contain all input beyond the last matched delimiter.
The string boo:and:foo, for example, yields the following results with these parameters:
Regex Limit Result
: 2 { "boo", "and:foo" }
: 5 { "boo", "an...
Do you use source control for your database items? [closed]
...your database under version control. Check the series of posts by K. Scott Allen.
When it comes to version control, the database is often a second or even third-class citizen. From what I've seen, teams that would never think of writing code without version control in a million years-- and right...
Django filter versus get for single object?
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get() is provided specifically for this case. Use it.
Option 2 is almost precisely how the get() method is actually implemented in Django, so there should be no "performance" difference (and the fact that you're thinking about it indicates you're vio...