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What is the difference between “def” and “val” to define a function
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Method def even evaluates on call and creates new function every time (new instance of Function1).
def even: Int => Boolean = _ % 2 == 0
even eq even
//Boolean = false
val even: Int => Boolean = _ % 2 == 0
even eq even
//Boolean = true
With def you ...
Get file size, image width and height before upload
How can I get the file size, image height and width before upload to my website, with jQuery or JavaScript?
7 Answers
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Suppress command line output
... the invocation to this:
taskkill /im "test.exe" /f >nul 2>&1
and all will be better.
That works because stdout is file descriptor 1, and stderr is file descriptor 2 by convention. (0 is stdin, incidentally.) The 2>&1 copies output file descriptor 2 from the new value of 1, whic...
Node.js - Find home directory in platform agnostic way
...indows a user's home directory might be C:\Users[USERNAME] or C:\Documents and Settings[USERNAME] depending on which version of Windows is being used. On Unix this isn't an issue.
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what is the difference between a portlet and a servlet?
I am asked to work on portlets and portals.
5 Answers
5
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CSS Div stretch 100% page height
I have a navigation bar on the left hand side of my page, and I want it to stretch to 100% of the page height. Not just the height of the viewport, but including the areas hidden until you scroll. I don't want to use javascript to accomplish this.
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How to combine multiple conditions to subset a data-frame using “OR”?
... the following syntax before with lot of success when I wanted to use the "AND" condition.
3 Answers
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How to read data when some numbers contain commas as thousand separator?
... some of the numerical values are expressed as strings with commas as thousand separator, e.g. "1,513" instead of 1513 . What is the simplest way to read the data into R?
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Why a function checking if a string is empty always returns true? [closed]
I have a function isNotEmpty which returns true if the string is not empty and false if the string is empty. I've found out that it is not working if I pass an empty string through it.
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In Hibernate Validator 4.1+, what is the difference between @NotNull, @NotEmpty, and @NotBlank?
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@NotEmpty: The CharSequence, Collection, Map or Array object is not null and size > 0.
@NotBlank: The string is not null and the trimmed length is greater than zero.
To help you understand, let's look into how these constraints are defined and carried out (I'm using version 4.1):
The @Not...