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What is a higher kinded type in Scala?
...at you don't have access to.)
"Higher-order" is simply a generic term that means repeated use of polymorphism/abstraction. It means the same thing for polymorphic types and values. Concretely, a higher-order abstraction abstracts over something that abstracts over something. For types, the term "hig...
How does the Comma Operator work
...lizers for symbol tables. Thus, it makes the following syntax possible and meaningful:
keywords = "and", "or", "not", "xor";
Notice that due to operator precedence, the code is (intentionally!) identical to
(((keywords = "and"), "or"), "not"), "xor";
That is, the first operator called is keywo...
Cleanest and most Pythonic way to get tomorrow's date?
...rlesWood: this answer may return a different hour that (in some timezones) means it may return a different date (not tomorrow) but it always returns the time that is exactly 24 hours ahead (the accepted answer returns midnight (unknown hours from now)). I don't see how leap seconds can change the re...
SQL Add foreign key to existing column
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Error indicates that there is no UserID column in your Employees table. Try adding the column first and then re-run the statement.
ALTER TABLE Employees
ADD CONSTRAINT FK_ActiveDirectories_UserID FOREIGN KEY (UserID)
REFERENCES ActiveDirectories(id);
...
How to enter in a Docker container already running with a new TTY
...le to access the container from another shell in order to "poke around" inside it and examine the files. At the moment, if I attach to the container, I am left looking at the Apache daemon and cannot run any commands.
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What is a tracking branch?
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Thanks! What I meant was posting them on your blog or something :). Thanks again for nice notes!
– Aditya
Jun 22 at 15:00
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Confusion: @NotNull vs. @Column(nullable = false) with JPA and Hibernate
...t says a JPA provider must recognize JSR 303 annotations, but that doesn't mean that other providers don't. I can't say whether any does or doesn't.
– Ryan Stewart
Sep 16 '11 at 2:59
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How to determine if a record is just created or updated in after_save
...king to use this for an after_save callback.
A simpler solution is to use id_changed? (since it won't change on update) or even created_at_changed? if timestamp columns are present.
Update: As @mitsy points out, if this check is needed outside of callbacks then use id_previously_changed?. See docs...
What is the difference between lemmatization vs stemming?
...,
and therefore cannot discriminate between words which have different
meanings depending on part of speech. However, stemmers are typically
easier to implement and run faster, and the reduced accuracy may not
matter for some applications.
For instance:
The word "better" has "go...
When to use .First and when to use .FirstOrDefault with LINQ?
... @driis - I'd imagine we can use the mantra of the exceptional exception guideline when choosing between First and FirstOrDefault. Thanks for the clear answer.
– Metro Smurf
Jun 21 '09 at 21:21
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