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Allowed characters in Linux environment variable names
...f code), here are a few hints to find the relevant lines of code: subst.c: param_expand(), in the default case -> general.h: /* Define exactly what a legal shell identifier consists of. */ #define legal_variable_starter(c) (ISALPHA(c) || (c == '')) #define legal_variable_char(c) (ISALNUM(c) || c ...
How to load a tsv file into a Pandas DataFrame?
...stead, i used read_table(), which worked much faster and without the extra param.
– Yurik
Aug 15 '14 at 9:56
...
Rails Observer Alternatives for 4.0
...stsController < ApplicationController
def create
@post = Post.new(params[:post])
@post.subscribe(PusherListener.new)
@post.subscribe(ActivityListener.new)
@post.subscribe(StatisticsListener.new)
@post.on(:create_post_successful) { |post| redirect_to post }
@post.on(:cr...
How to normalize a path in PowerShell?
...
The parameters for [io.path]::Combine are reversed. Better yet, use the native Join-Path PowerShell command: Join-Path (Resolve-Path ..\frag).Path 'fred\frog' Also note that, at least as of PowerShell v3, Resolve-Path now support...
Change date format in a Java string
...DateFormat; import java.util.Date; public class formateDate { /** * @param args * @throws ParseException */ public static void main(String[] args) throws ParseException { // TODO Auto-generated method stub String date_s=" 2011-01-18 00:00:00.0"; SimpleDateFormat dt= new SimpleDate...
Why is it Valid to Concatenate Null Strings but not to Call “null.ToString()”?
... String.Concat in Reflector, you'll see it:
// while looping through the parameters
strArray[i] = (str == null) ? Empty : str;
// then concatenate that string array
(MSDN mentions it, too: http://msdn.microsoft.com/en-us/library/k9c94ey1.aspx)
On the other hand, ToString() is an instance meth...
Single vs Double quotes (' vs ")
...as JavaScript within an attribute, for example:
<button onClick='func("param");'>Press Me</button>
Of course if we are in PHP and want the parser to handle PHP variables within the string we should intentionally use double quotes. $a='Awesome'; $b = "Not $a";
Sources
Single quotes vs...
Adding a directory to the PATH environment variable in Windows
...function. Just supply the directory you wish to add:
function AddTo-Path{
param(
[string]$Dir
)
if( !(Test-Path $Dir) ){
Write-warning "Supplied directory was not found!"
return
}
$PATH = [Environment]::GetEnvironmentVariable("PATH")
if( $PATH -notlike "*"+$Dir+...
Check number of arguments passed to a Bash script
...between its arguments.
if [ "$#" -ne 1 ]; then
echo "Illegal number of parameters"
fi
Or
if test "$#" -ne 1; then
echo "Illegal number of parameters"
fi
Suggestions
When in Bash, prefer using [[ ]] instead as it doesn't do word splitting and pathname expansion to its variables that quoting...
Calling constructor from other constructor in same class
...
Append :this(required params) at the end of the constructor to do 'constructor chaining'
public Test( bool a, int b, string c )
: this( a, b )
{
this.m_C = c;
}
public Test( bool a, int b, float d )
: this( a, b )
{
this.m_D = d;
...