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How to upgrade all Python packages with pip?
Is it possible to upgrade all Python packages at one time with pip ?
55 Answers
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remove all variables except functions
I have loaded in a R console different type of objects.
I can remove them all using
5 Answers
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Using Git, show all commits that are in one branch, but not the other(s)
...ich I would like to delete. However, before doing so, I want to check that all commits made to this branch were at some point merged into some other branch. Thus, I'd like to see all commits made to my current branch which have not been applied to any other branch [or, if this is not possible withou...
How to fix the Hibernate “object references an unsaved transient instance - save the transient insta
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You should include cascade="all" (if using xml) or cascade=CascadeType.ALL (if using annotations) on your collection mapping.
This happens because you have a collection in your entity, and that collection has one or more items which are not present in ...
What's the difference between INNER JOIN, LEFT JOIN, RIGHT JOIN and FULL JOIN? [duplicate]
...- the join can be one->one, one->many, or many->many. So it's actually impossible to represent with a Venn diagram: all this diagram does is show you "what portion of the table will be involved in the join." In which case select a.* from a cross join b should have the same diagram as full o...
Why should I prefer single 'await Task.WhenAll' over multiple awaits?
...n case I do not care about the order of task completion and just need them all to complete, should I still use await Task.WhenAll instead of multiple await ? e.g, is DoWork2 below a preferred method to DoWork1 (and why?):
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How to get all Errors from ASP.Net MVC modelState?
I want to get all the error messages out of the modelState without knowing the key values. Looping through to grab all the error messages that the ModelState contains.
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Soft hyphen in HTML ( vs. ­)
...ly, &shy's support is so inconsistent between browsers that it can't really be used.
QuirksMode is right -- there's no good way to use soft hyphens in HTML right now. See what you can do to go without them.
2013 edit: According to QuirksMode, ­ now works/is supported on all major brows...
Highlight all occurrence of a selected word?
How can I highlight all occurrence of a selected word in GVim, like in Notepad++?
15 Answers
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How to tell if a string is not defined in a Bash shell script
... not set, you can use:
if [ -z "${VAR+xxx}" ]; then echo VAR is not set at all; fi
if [ -z "$VAR" ] && [ "${VAR+xxx}" = "xxx" ]; then echo VAR is set but empty; fi
You probably can combine the two tests on the second line into one with:
if [ -z "$VAR" -a "${VAR+xxx}" = "xxx" ]; then echo VA...