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Like Operator in Entity Framework?
...attern in a specified expression, or zeros if the pattern is not found, on all valid text and character data types
Namespace: System.Data.Objects.SqlClient
Assembly: System.Data.Entity (in System.Data.Entity.dll)
A bit of an explanation also appears in this forum thread.
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How to perform runtime type checking in Dart?
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The instanceof-operator is called is in Dart. The spec isn't exactly friendly to a casual reader, so the best description right now seems to be http://www.dartlang.org/articles/optional-types/.
Here's an example:
class Foo { }
main() {
var foo = ne...
What is meant by 'first class object'?
...nction
literal) if it treats functions as
first-class objects. Specifically,
this means that the language supports
constructing new functions during the
execution of a program, storing them
in data structures, passing them as
arguments to other functions, and
returning them as the va...
“Single-page” JS websites and SEO
... the server act as an API (and nothing more) and letting the client handle all of the HTML generation stuff. The problem with this "pattern" is the lack of search engine support. I can think of two solutions:
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How to move a file?
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os.rename(), shutil.move(), or os.replace()
All employ the same syntax:
import os
import shutil
os.rename("path/to/current/file.foo", "path/to/new/destination/for/file.foo")
shutil.move("path/to/current/file.foo", "path/to/new/destination/for/file.foo")
os.replace("p...
How to display pandas DataFrame of floats using a format string for columns?
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As of Pandas 0.17 there is now a styling system which essentially provides formatted views of a DataFrame using Python format strings:
import pandas as pd
import numpy as np
constants = pd.DataFrame([('pi',np.pi),('e',np.e)],
columns=['name','value'])
C = constants...
Spring MVC: How to perform validation?
...out that: I saw it validates a class. Does the class have to be filled manually with the values from the user input, and then passed to the validator?
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Type Checking: typeof, GetType, or is?
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All are different.
typeof takes a type name (which you specify at compile time).
GetType gets the runtime type of an instance.
is returns true if an instance is in the inheritance tree.
Example
class Animal { }
class Do...
What is “lifting” in Haskell?
...ill now refute me by showing how lifts are a category or something).
Typically you have some data type with a parameter. Something like
data Foo a = Foo { ...stuff here ...}
Suppose you find that a lot of uses of Foo take numeric types (Int, Double etc) and you keep having to write code that un...
What is the exact meaning of IFS=$'\n'?
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Normally bash doesn't interpret escape sequences in string literals. So if you write \n or "\n" or '\n', that's not a linebreak - it's the letter n (in the first case) or a backslash followed by the letter n (in the other two cas...