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Does Ruby regular expression have a not match operator like “!~” in Perl?
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3 Answers
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“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
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1003
I would recommend using INSERT...ON DUPLICATE KEY UPDATE.
If you use INSERT IGNORE, then the ro...
Resize image proportionally with MaxHeight and MaxWidth constraints
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3 Answers
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Active
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What's the difference between a proc and a lambda in Ruby?
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An example:
p = Proc.new {|a, b| puts a**2+b**2 } # => #<Proc:0x3c7d28@(irb):1>
p.call 1, 2 # => 5
p.call 1 # => NoMethodError: undefined method `**' for nil:NilClass
p.call 1, 2, 3 # => 5
l = lambda {|a, b| puts a**2+b**2 } # => #<Proc:0x15016c@(irb):5 (lambda)>
l.ca...
Choosing a file in Python with simple Dialog
...ng tkinter?
from Tkinter import Tk # from tkinter import Tk for Python 3.x
from tkinter.filedialog import askopenfilename
Tk().withdraw() # we don't want a full GUI, so keep the root window from appearing
filename = askopenfilename() # show an "Open" dialog box and return the path to the select...
Is it possible to decompile a compiled .pyc file into a .py file?
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173
Uncompyle6 works for Python 3.x and 2.7 - recommended option as it's most recent tool, aiming to...
What is tail recursion?
...ple function that adds the first N natural numbers. (e.g. sum(5) = 1 + 2 + 3 + 4 + 5 = 15).
Here is a simple JavaScript implementation that uses recursion:
function recsum(x) {
if (x === 1) {
return x;
} else {
return x + recsum(x - 1);
}
}
If you called recsum(5), th...
how to get android screen size programmatically, once and for all?
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edited Sep 10 '13 at 7:13
Ankur
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answ...
Select every Nth element in CSS
...;/h1>
<div>1</div> <div>2</div>
<div>3</div> <div>4</div>
<h2></h2>
<div>5</div> <div>6</div>
<div>7</div> <div>8</div>
<h2></h2>
<div>9</div> <...