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Add custom messages in assert?
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Another option is to reverse the operands and use the comma operator. You need extra parentheses so the comma isn't treated as a delimiter between the arguments: assert(("A must be equal to B", a == b));
– Keith Thompson
J...
Replace a value if null or undefined in JavaScript
I have a requirement to apply the ?? C# operator to JavaScript and I don't know how.
Consider this in C#:
5 Answers
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remove legend title in ggplot
... all legend titles. For more local control, the guide = guide_legend() command works. To remove the fill legend title, but to keep the color legend title, e.g. scale_fill_brewer(palette = "Dark2", guide = guide_legend(title = NULL)) + scale_color_manual(values = c("blue", "white", "red"))
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How to add column if not exists on PostgreSQL?
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Here's a short-and-sweet version using the "DO" statement:
DO $$
BEGIN
BEGIN
ALTER TABLE <table_name> ADD COLUMN <column_name> <column_type>;
EXCEPTION
WHEN duplicate_column THE...
How to call shell commands from Ruby
How do I call shell commands from inside of a Ruby program? How do I then get output from these commands back into Ruby?
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The breakpoint will not currently be hit. No symbols have been loaded for this document in a Silverl
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i have multiple projects and start them as u tell.. some of them are class library projects.. follwing error popup appears: "A project with an Output Type of Class Library cannot be started directly"
– Muhammad Azeem
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Xcode : failed to get the task for process
This is for an existing app that compiled and distributed multiple times. Since updating to Xcode 5 I have this error popping.
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Windows equivalent to UNIX pwd
How do I find the local path on windows in a command prompt?
10 Answers
10
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Cost of storing AMI
I understand Amazon will charge per GB provisioned EBS storage. If I create AMI of my instance, does this mean my EBS volume will be duplicated, and hence incur additional cost?
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How do I import an SQL file using the command line in MySQL?
...om phpMyAdmin . I want to import it into a different server using the command line.
49 Answers
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