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What does Class mean in Java?
... when you use it with Class. Both lines work and compile:
Class anyType = String.class;
Class <?> theUnknownType = String.class;
But - if we start using it with collections, then we see strange compiletime errors:
List<?> list = new ArrayList<Object>(); // ArrayList<?> i...
Jinja2 template variable if None Object set a default value
...p.User['first_name'] if p != None else 'NONE' }}
or if you need an empty string:
{{ p.User['first_name'] if p != None }}
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Why aren't Java Collections remove methods generic?
...h is predicates. Consider the following sample:
class Person {
public String name;
// override equals()
}
class Employee extends Person {
public String company;
// override equals()
}
class Developer extends Employee {
public int yearsOfExperience;
// override equals()
}
cl...
How do I generate a constructor from class fields using Visual Studio (and/or ReSharper)?
...MTypeRefVoid, position, parentConstructor.Access)
Dim baseCall As String = ":base("
Dim separator As String = ""
For Each parameter As CodeParameter2 In parentConstructor.Parameters
ctor.AddParameter(parameter.Name, parameter.Type, -1)
baseCall += sep...
What is the preferred syntax for initializing a dict: curly brace literals {} or the dict() function
...xample, say {1: 'one', 2: 'two'}. The second variant only works for (some) string keys. Using different kinds of syntax depending on the type of the keys would be an unnecessary inconsistency.
It is faster:
$ python -m timeit "dict(a='value', another='value')"
1000000 loops, best of 3: 0.79 usec pe...
A variable modified inside a while loop is not remembered
...will not be available once the subshell exits.
Instead you can use a here string to re-write the while loop to be in the main shell process; only echo -e $lines will run in a subshell:
while read line
do
if [[ "$line" == "second line" ]]
then
foo=2
echo "Variable \$foo upda...
Convert HTML to PDF in .NET
... nuget package.
Use Example Method.
public static Byte[] PdfSharpConvert(String html)
{
Byte[] res = null;
using (MemoryStream ms = new MemoryStream())
{
var pdf = TheArtOfDev.HtmlRenderer.PdfSharp.PdfGenerator.GeneratePdf(html, PdfSharp.PageSize.A4);
pdf.Save(ms);
...
Java FileOutputStream Create File if not exists
Is there a way to use FileOutputStream in a way that if a file (String filename) does not exist, then it will create it?
9 ...
LINQ with groupby and count
...ready have a list/array of some class that looks like
class UserInfo {
string name;
int metric;
..etc..
}
...
List<UserInfo> data = ..... ;
When you do data.GroupBy(x => x.metric), it means "for each element x in the IEnumerable defined by data, calculate it's .metric, then gr...
How to check if a variable exists in a FreeMarker template?
... This only check if the var exists. But if you have an empty String in "userName", the <#if userName??> will return true !! See @user1546081 answer on this page to address this issue.
– Adrien Be
Jan 15 '13 at 10:22
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