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The cast to value type 'Int32' failed because the materialized value is null
...ky abstraction" that yields unexpected behaviour.
One such case is null handling, where there can be unexpected nulls in different places. ...DefaultIfEmpty(0).Sum(0) can help in this (quite simple) case, where there might be no elements and sql's SUM returns null whereas c# expect 0.
A more gene...
Is False == 0 and True == 1 an implementation detail or is it guaranteed by the language?
Is it guaranteed that False == 0 and True == 1 , in Python (assuming that they are not reassigned by the user)? For instance, is it in any way guaranteed that the following code will always produce the same results, whatever the version of Python (both existing and, likely, future ones)?
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Any way to delete in vim without overwriting your last yank? [duplicate]
...help registers.
It's probably safest, if you want to paste something over and over again, to yank it into a "named" register.
"aY
Yanks a line into the a register. Paste it with "ap.
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Handling colon in element ID with jQuery
...xplanation:
Apart from the speed gain (see further down), it is easier to handle.
Example: Say you have a function
function doStuff(id){
var jEle = $("#" + id); //is not safe, since id might be "foo:bar:baz" and thus fail.
//You would first have to look for ":" in the id string,...
Should I store entire objects, or pointers to objects in containers?
Designing a new system from scratch. I'll be using the STL to store lists and maps of certain long-live objects.
10 Answer...
Renaming a branch in GitHub
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As mentioned, delete the old one on GitHub and re-push, though the commands used are a bit more verbose than necessary:
git push origin :name_of_the_old_branch_on_github
git push origin new_name_of_the_branch_that_is_local
Dissecting the commands a bit, the git push ...
Have the same README both in Markdown and reStructuredText
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I would recommend Pandoc, the "swiss-army knife for converting files from one markup format into another" (check out the diagram of supported conversions at the bottom of the page, it is quite impressive). Pandoc allows markdown to reStructured...
How can I refresh a page with jQuery?
... This didn't work for me. window.location.href=window.location.href; and location.href=location.href; worked.
– twharmon
Oct 6 '16 at 6:40
23
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How to insert a value that contains an apostrophe (single quote)?
...r single quote, is a special character in SQL that specifies the beginning and end of string data. This means that to use it as part of your literal string data you need to escape the special character. With a single quote this is typically accomplished by doubling your quote. (Two single quote char...
I forgot the password I entered during postgres installation
...assword to the default user of Postgres. I can't seem to be able to run it and I get the following error:
13 Answers
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