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What is the correct syntax for 'else if'?
...om 2.6.4 to 3.1.1. Everything has gone fine until I tried to use the 'else if' statement. The interpreter gives me a syntax error after the 'if' in 'else if' for a reason I can't seem to figure out.
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Kotlin Ternary Conditional Operator
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In Kotlin, if statements are expressions. So the following code is equivalent:
if (a) b else c
The distinction between expression and statement is important here. In Java/C#/JavaScript, if forms a statement, meaning that it does not ...
Check if table exists in SQL Server
I would like this to be the ultimate discussion on how to check if a table exists in SQL Server 2000/2005 using SQL Statements.
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How to avoid 'cannot read property of undefined' errors?
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Update:
If you use JavaScript according to ECMAScript 2020 or later, see optional chaining.
TypeScript has added support for optional chaining in version 3.7.
// use it like this
obj?.a?.lot?.of?.properties
Solution for JavaScr...
How to find out if an item is present in a std::vector?
...ind(vec.begin(), vec.end(), item) != vec.end()
This returns a bool (true if present, false otherwise). With your example:
#include <algorithm>
#include <vector>
if ( std::find(vec.begin(), vec.end(), item) != vec.end() )
do_this();
else
do_that();
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if…else within JSP or JSTL
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Should I use JSTL ?
Yes.
You can use <c:if> and <c:choose> tags to make conditional rendering in jsp using JSTL.
To simulate if , you can use:
<c:if test="condition"></c:if>
To simulate if...else, you can use:
<c:choose>
<c:wh...
Create PostgreSQL ROLE (user) if it doesn't exist
...QL script to create a ROLE in PostgreSQL 9.1, but without raising an error if it already exists?
10 Answers
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Check if two unordered lists are equal [duplicate]
I'm looking for an easy (and quick) way to determine if two unordered lists contain the same elements:
8 Answers
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C# Test if user has write access to a folder
I need to test if a user can write to a folder before actually attempting to do so.
18 Answers
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How to check if an object is an array?
...rite a function that either accepts a list of strings, or a single string. If it's a string, then I want to convert it to an array with just the one item so I can loop over it without fear of an error.
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