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Fixed point vs Floating point number
...lled the exponent). So a floating point number that took up 10 digits with 2 digits reserved for the exponent might represent a largest value of 9.9999999e+50 and a smallest non-zero value of 0.0000001e-49.
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What is an idempotent operation?
...ome incorrect and misleading examples. Comments below written before April 2014 refer to an older revision.
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Gson - convert from Json to a typed ArrayList
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529
You may use TypeToken to load the json string into a custom object.
logs = gson.fromJson(br, n...
Invalid argument supplied for foreach()
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edited Oct 27 '15 at 20:57
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#1071 - Specified key was too long; max key length is 1000 bytes
... left substring of the data. Most of your data will be a lot shorter than 255 characters anyway.
You can declare a prefix length per column as you define the index. For example:
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KEY `index` (`parent_menu_id`,`menu_link`(50),`plugin`(50),`alias`(50))
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But what's the best prefix length fo...
ImportError: no module named win32api
I am using Python 2.7 and I want to use pywin32-214 on Windows 7 . I installed pywin32-214 by using the msi installer. But when I import win32api in my Python script, it throws the error:
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catch all unhandled exceptions in ASP.NET Web Api
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This is now possible with WebAPI 2.1 (see the What's New):
Create one or more implementations of IExceptionLogger. For example:
public class TraceExceptionLogger : ExceptionLogger
{
public override void Log(ExceptionLoggerContext context)
{
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I want to get the type of a variable at runtime
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132
So, strictly speaking, the "type of a variable" is always present, and can be passed around as a...
Direct casting vs 'as' operator?
... Otherwise, assigns o to s, even if o is null.
string s = o as string; // 2
Assigns null to s if o is not a string or if o is null. For this reason, you cannot use it with value types (the operator could never return null in that case). Otherwise, assigns o to s.
string s = o.ToString(); // 3
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Rails: how do I validate that something is a boolean?
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Since Rails 3, you can do:
validates :field, inclusion: { in: [ true, false ] }
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