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delete map[key] in go?
...sions = map[string] chan int{};
sessions["moo"] = make (chan int);
_, ok := sessions["moo"];
if ok {
delete(sessions, "moo");
}
}
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Regarding 'main(int argc, char *argv[])' [duplicate]
...hat it matters much anymore but just a fun fact that I happen to remember ^_^
– Frank
Feb 24 '18 at 9:31
@JesseChishol...
“unpacking” a tuple to call a matching function pointer
...<<b<<" "<<c<< std::endl; };
auto params = std::make_tuple(1,2.0,"Hello");
std::apply(f, params);
Just felt that should be stated once in an answer in this thread (after it already appeared in one of the comments).
The basic C++14 solution is still missing in this thread....
How to get current time and date in C++?
...
In C++ 11 you can use std::chrono::system_clock::now()
Example (copied from en.cppreference.com):
#include <iostream>
#include <chrono>
#include <ctime>
int main()
{
auto start = std::chrono::system_clock::now();
// Some computation ...
How to include file in a bash shell script
...t . is POSIX compliant whereas source isn't
– Mathieu_Du
Feb 20 '15 at 19:38
But here source is not exactly the includ...
How to write DataFrame to postgres table?
There is DataFrame.to_sql method, but it works only for mysql, sqlite and oracle databases. I cant pass to this method postgres connection or sqlalchemy engine.
...
What is the python “with” statement designed for?
...rom contextlib import contextmanager
import os
@contextmanager
def working_directory(path):
current_dir = os.getcwd()
os.chdir(path)
try:
yield
finally:
os.chdir(current_dir)
with working_directory("data/stuff"):
# do something within data/stuff
# here I am back...
Print text instead of value from C enum
...
I use something like this:
in a file "EnumToString.h":
#undef DECL_ENUM_ELEMENT
#undef DECL_ENUM_ELEMENT_VAL
#undef DECL_ENUM_ELEMENT_STR
#undef DECL_ENUM_ELEMENT_VAL_STR
#undef BEGIN_ENUM
#undef END_ENUM
#ifndef GENERATE_ENUM_STRINGS
#define DECL_ENUM_ELEMENT( element ) element,
#...
argparse store false if unspecified
...
The store_true option automatically creates a default value of False.
Likewise, store_false will default to True when the command-line argument is not present.
The source for this behavior is succinct and clear: http://hg.python.or...
How do I update the notification text for a foreground service in Android?
... only by calling stopForground );
Example:
private static final int NOTIF_ID=1;
@Override
public void onCreate (){
this.startForeground();
}
private void startForeground() {
startForeground(NOTIF_ID, getMyActivityNotification(""));
}
private Notification getMyActivityNotification(String...