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Overriding superclass property with different type in Swift
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Swift does not allow you to change the class type of any variables or properties. Instead you can create an extra variable in the subclass that handles the new class type:
class Chassis {}
class RacingChassis : Chassis {}
class Car {
...
Which characters need to be escaped when using Bash?
...h but also bash.
1. Put the whole string in single quotes
This works for all chars except single quote itself. To escape the single quote, close the quoting before it, insert the single quote, and re-open the quoting.
'I'\''m a s@fe $tring which ends in newline
'
sed command: sed -e "s/'/'\\\\'...
Why #define TRUE (1==1) in a C boolean macro instead of simply as 1?
...type (and resolve to true and false) if the compiler supports it. (specifically, C++)
However, it would be better to check whether C++ is in use (via the __cplusplus macro) and actually use true and false.
In a C compiler, this is equivalent to 0 and 1.
(note that removing the parentheses will bre...
Troubleshooting “Illegal mix of collations” error in mysql
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This is generally caused by comparing two strings of incompatible collation or by attempting to select data of different collation into a combined column.
The clause COLLATE allows you to specify the collation used in the query.
For exa...
What is the meaning and difference between subject, user and principal?
...utomation, applications, connections, etc.
User - A subset of principal usually referring to a human operator. The distinction is blurring over time because the words "user" or "user ID" are commonly interchanged with "account". However, when you need to make the distinction between the broad clas...
How can I debug git/git-shell related problems?
...SS=2 GIT_TRACE_PACKET=2 GIT_TRACE_PACKFILE=2 GIT_TRACE_SETUP=2 GIT_TRACE_SHALLOW=2 git pull origin master -v -v; set +x
– Paul Irish
Jan 9 '16 at 21:22
2
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How to re-create database for Entity Framework?
...ed, if so, right click and delete.
2 )Go to Solution Explorer, click show All Files icon.
3) Go to App_Data, right click and delete all ".mdf" files for this project.
4) Delete Migrations folder by right click and delete.
5) Go to SQL Server Management Studio, make sure the DB for this project i...
How to drop unique in MySQL?
...swered Oct 14 '09 at 8:12
Wael DalloulWael Dalloul
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Abort makefile if variable not set
... an auxiliary function for that:
# Check that given variables are set and all have non-empty values,
# die with an error otherwise.
#
# Params:
# 1. Variable name(s) to test.
# 2. (optional) Error message to print.
check_defined = \
$(strip $(foreach 1,$1, \
$(call __check_defined,$...
Extracting text OpenCV
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For some cards the bounding box does not enclose all of the text, such as half a letter getting cut off. Such as this card: i.imgur.com/tX3XrwH.jpg How can I extend every bounding bounding boxes height and width by n? Thanks for the solution it works great!
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