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What is /dev/null 2>&1?
...ns three files, standard input, standard output, and standard error as we know whenever a file is opened, the operating system (from kernel) returns a non-negative integer called a file descriptor. The file descriptor for these files are 0, 1, and 2, respectively.
So 2>&1 simply says redirec...
Why does PHP consider 0 to be equal to a string?
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I see. This now works (with a typecast): if((string)$item['price']=='e'){ $item['price'] = -1; }
– Sérgio Domingues
Jul 27 '11 at 10:54
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How can I get the list of a columns in a table for a SQLite database?
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Great! Now how is this done from outside the command line? How is this done from within my own C program?
– Aaron Bratcher
Sep 27 '13 at 13:56
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“Variable” variables in Javascript?
I know it's possible in PHP to have "variable" variables. For example
7 Answers
7
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Tainted canvases may not be exported
...r me
img.src = src;
return img;
}
And in your callback you can now use ctx.drawImage and export it using toDataURL
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List comprehension in Ruby
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Actually I see now the OP itself had some existing list the author wanted to transform. But the archetypal conception of list comprehension involves creating an array/list where one didn't exist before by referencing some iteration. But a...
Showing the same file in both columns of a Sublime Text window
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@MattDMo , I see what you meant now. How do I remove the down vote?
– LED Fantom
Oct 22 '16 at 2:28
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YAML current date in rmarkdown
...lt;%= format(Sys.time(), "%d %B, %Y") %>
author: baptiste
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You can now use a brew_n_render function that would preprocess the doc using brew and then run in through rmarkdown.
brew_n_render <- function(input, ...){
output_file <- gsub("\\.[R|r]md$", ".html", input)
brew::brew(inpu...
How to get enum value by string or int
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Now also add a this to the parameter and make EnumHelper static and you can use them as extensions too (see my answer, but you have a better/complete code for the rest)...
– Christoph Fink
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How do I purge a linux mail box with huge number of emails? [closed]
I have setup some cron jobs and they send the crons result to an email. Now over the months I have accumulated a huge number of emails.
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