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What is the argument for printf that formats a long?
...
printf("%ld", ULONG_MAX) outputs the value as -1. Should be printf("%lu", ULONG_MAX) for unsigned long as described by @Blorgbeard below.
– jammus
Nov 12 '11 at 16:03
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Rake just one migration
...n dropped from the database outside of Rails, rake db:migrate:up VERSION=my_version may do nothing, because the schema_migrations table still says it is has been run. In the same situation rake db:migrate:redo VERSION=my_version may fail because it cannot drop the table. In this case, comment out th...
Ruby convert Object to Hash
...book"
@price = 15.95
end
end
gift = Gift.new
hash = {}
gift.instance_variables.each {|var| hash[var.to_s.delete("@")] = gift.instance_variable_get(var) }
p hash # => {"name"=>"book", "price"=>15.95}
Alternatively with each_with_object:
gift = Gift.new
hash = gift.instance_variable...
`from … import` vs `import .` [duplicate]
... for simplicity or to avoid masking built ins:
from os import open as open_
# lets you use os.open without destroying the
# built in open() which returns file handles.
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How do I get Gridview to render THEAD?
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I use this in OnRowDataBound event:
protected void GridViewResults_OnRowDataBound(object sender, GridViewRowEventArgs e) {
if (e.Row.RowType == DataControlRowType.Header) {
e.Row.TableSection = TableRowSection.TableHeader;
}
}
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How do I update Ruby Gems from behind a Proxy (ISA-NTLM)
...e command-line switch but I have been able to do it just by setting my HTTP_PROXY environment variable. (Note that case seems to be important). I have a batch file that has a line like this in it:
SET HTTP_PROXY=http://%USER%:%PASSWORD%@%SERVER%:%PORT%
I set the four referenced variables before I...
How to get UILabel to respond to tap?
...= UITapGestureRecognizer(target: self, action: #selector(self.actionTapped(_:)))
tempLabel?.isUserInteractionEnabled = true
tempLabel?.addGestureRecognizer(tapAction)
Action receiver
func actionTapped(_ sender: UITapGestureRecognizer) {
// code here
}
Swift 4.0
Initialize the gesture...
How to delete migration files in Rails 3
...rt DB changes due to this migration)
Run "rails destroy migration migration_name" (migration_name is the one use chose while creating migration. Remove "timestamp_" from your migration file name to get it)
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How to Select Every Row Where Column Value is NOT Distinct
...r be used in an aggregate function error. Is the only fix - editing the sql_mode?
– Volodymyr Bobyr
Jul 16 at 16:21
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How do I get the application exit code from a Windows command line?
...cial syntax:
if errorlevel
See if /? for details.
Example
@echo off
my_nify_exe.exe
if errorlevel 1 (
echo Failure Reason Given is %errorlevel%
exit /b %errorlevel%
)
Warning: If you set an environment variable name errorlevel, %errorlevel% will return that value and not the exit code. ...