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What's the syntax for mod in java
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Instead of the modulo operator, which has slightly different semantics, for non-negative integers, you can use the remainder operator %. For your exact example:
if ((a % 2) == 0)
{
isEven = true;
}
else
{
isEven = false;
}
This can be simplif...
Rails: call another controller action from a controller
...use a redirect to that action :
redirect_to your_controller_action_url
More on : Rails Guide
To just render the new action :
redirect_to your_controller_action_url and return
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Redefining NULL
I'm writing C code for a system where address 0x0000 is valid and contains port I/O. Therefore, any possible bugs that access a NULL pointer will remain undetected and at the same time cause dangerous behaviour.
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Importing CSV with line breaks in Excel 2007
I'm working on a feature to export search results to a CSV file to be opened in Excel. One of the fields is a free-text field, which may contain line breaks, commas, quotations, etc. In order to counteract this, I have wrapped the field in double quotes (").
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Why use Ruby instead of Smalltalk? [closed]
...n Ruby and Smalltalk -- maglev is a testament to that. Despite having a more unusual syntax, Smalltalk has all (if not more) of the object-oriented beauty of Ruby.
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Cannot add or update a child row: a foreign key constraint fails
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You're getting this error because you're trying to add/update a row to table2 that does not have a valid value for the UserID field based on the values currently stored in table1. If you post some more code I can help you diagnose the specific caus...
Null or default comparison of generic argument in C#
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To avoid boxing, the best way to compare generics for equality is with EqualityComparer<T>.Default. This respects IEquatable<T> (without boxing) as well as object.Equals, and handles all the Nullable<T> "lifted" nuances. Hence:
if(EqualityComparer<T>....
Splitting a Java String by the pipe symbol using split(“|”)
...uses regular expression and in regex | is a metacharacter representing the OR operator. You need to escape that character using \ (written in String as "\\" since \ is also a metacharacter in String literals and require another \ to escape it).
You can also use
test.split(Pattern.quote("|"));
a...
To switch from vertical split to horizontal split fast in Vim
How can you switch your current windows from horizontal split to vertical split and vice versa in Vim?
8 Answers
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Undo scaffolding in Rails
...eady run the migrations generated by the scaffold command, you have to perform a rollback first.
rake db:rollback
You can create scaffolding using:
rails generate scaffold MyFoo
(or similar), and you can destroy/undo it using
rails destroy scaffold MyFoo
That will delete all the files cre...