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What's the safest way to iterate through the keys of a Perl hash?
...h of (key, value) pairs, what is the preferred method of iterating through all the keys? I have heard that using each may in some way have unintended side effects. So, is that true, and is one of the two following methods best, or is there a better way?
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Inputting a default image in case the src attribute of an html is not valid?
...body>
</html>
Since the first image doesn't exist, the fallback (the sprites used on this web site*) will display. And if you're using a really old browser that doesn't support object, it will ignore that tag and use the img tag. See caniuse website for compatibility. This element...
How can I have grep not print out 'No such file or directory' errors?
...u don't need to pass in -R or the path.
git grep pattern
That will show all matches from your current directory down.
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Ruby max integer
... determine a systems maximum integer in Ruby. Anybody know how, or if it's possible?
6 Answers
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Entity Framework and Connection Pooling
...tion Pooling (ADO.NET))
Never ever use global context. ObjectContext internally implements several patterns including Identity Map and Unit of Work. Impact of using global context is different per application type.
For web applications use single context per request. For web services use single con...
How do I make a list of data frames?
...to your question, but you want to use = and not <- within the function call. If you use <-, you'll end up creating variables y1 and y2 in whatever environment you're working in:
d1 <- data.frame(y1 <- c(1, 2, 3), y2 <- c(4, 5, 6))
y1
# [1] 1 2 3
y2
# [1] 4 5 6
This won't have the s...
How can I match multiple occurrences with a regex in JavaScript similar to PHP's preg_match_all()?
... comment: rather than using regex, we now have URLSearchParams, which does all of this for us, so no custom code, let alone regex, are necessary anymore.
– Mike 'Pomax' Kamermans
Browser support is listed here https://caniuse.com/#feat=urlsearchparams
I would suggest an alternative reg...
How to format date in angularjs
...dd/yyyy . I tried the following and none of it works for me.
Can anyone help me with this?
15 Answers
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Font-awesome, input type 'submit'
... to use some class from font-awesome for button input? I've added icons to all buttons (which actually links with class 'btn' from twitter-bootstrap) in my applications, but can't add icons on 'input type submit'.
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Android: Clear Activity Stack
... navigates to login Screen and from there user can exit by cancel button (calling system.exit(0) )
11 Answers
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