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/**
 * Return true only if the element is not null or undefined,
 * use it with `Array.filter` to not only filter nullable values
 * but also to guard the type.
 */
export const isDefined = <T>(argument: T | undefined | null): argument is T => {
  return argument !== undefined && argument !== null;
};

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let personList = `First_Name: John, Last_Name: Doe
First_Name: Jane, Last_Name: Smith`;

// Adding a ? at the end of the named capturing group makes it optional, e.g. '... (?<lastname>\w+)?'
let regexpNames =  /First_Name: (?<firstname>\w+), Last_Name: (?<lastname>\w+)/mg;
let match = regexpNames.exec(personList);
do {
  console.log(`Hello ${match.groups.firstname} ${match.groups.lastname}`);
} while((match = regexpNames.exec(personList)) !== null);

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// Script to run in the developer console from a GitHub Pull Request page to get the list of all commits titles and descriptions

"\n- " + $x('//code/a[@class="Link--secondary markdown-title"]').map(e => {
  let msg = e.title;
  const pars = msg.split("\n\n");
  if (pars.length > 1) {
    msg = pars[0] + (pars[0].endsWith(":") || pars[0].endsWith(".") ? "" : ":");  // commit title
    msg += "\n  ";
    msg += pars[1].split('\n').join('.\n  ');                                     // commit description
  }

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#!/usr/bin/env sh

# Get a file from a GitHub repository, trying first to download it
# from a branch passed by argument, if the file doesn't exist,
# fallback to another branch version.
#
# Script to be called from Github Actions as following:
#
#     - name: Get GitHub downloader
#       run: wget https://gist.github.com/mrsarm/95279381f3d8bf4269499fb437888e2c/raw/github-file.sh

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/// Multi-thread example in Rust of iterating a vector as input data in chunks,
/// using threads in a safe way, using the threads and the channels APIs, and
/// the `Arc` type.
///
/// ## Details
///
/// Spawn MAX_NTHREADS number of threads, then from each thread borrow a slice
/// of the vector data, and from each string inside
/// the slice, calculate a new string and publish it into a channel, that
/// can then be listened by a receiver from the main thread, while the

mrsarm

/**
 * Execute concurrently the asynchronous functions `fns` passed, but
 * not more than `maxConcurrency` at the same time. All functions
 * return the same type T, an a promise with T[] inside is returned.
 */
const execConcurrent = async<T> (
  fns: (() => Promise<T>)[],
  maxConcurrency: number,
): Promise<T[]> => {
  const res: T[] = [];

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-- Delete Database with connections opened

-- Postgres older than 13 don't support FORCE option, in this case pg_terminate_backend() is used:

SELECT pid, pg_terminate_backend(pid)
  FROM pg_stat_activity
  WHERE pg_stat_activity.datname = 'dbname';

DROP DATABASE dbname;

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#!/usr/bin/env bash

if [ "$1" == "-h" -o "$1" == "--help" -o "$#" == "0" ]
then
    echo "Convert what ever video file to a compatible MP4 file"
    echo "that works on most devices."
    echo
    echo "Usage: video2mp4.sh [FILE]"
    exit
fi

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Install Python from sources

On Ubuntu or compatible:

sudo apt-get install build-essential libsqlite3-dev sqlite3 bzip2 libbz2-dev zlib1g-dev libssl-dev libffi-dev lzma liblzma-dev

Download Python source and install as normal user with (replace prefix path, e.g. /opt/py/python3.11):

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-- DB size in bytes
SELECT pg_size_pretty( pg_database_size('dbname') );

-- Table size in bytes
SELECT pg_size_pretty( pg_total_relation_size('tablename') );


-- All table sizes sorted by size desc
SELECT table_name, pg_size_pretty( pg_relation_size(quote_ident(table_name)) )
  FROM information_schema.tables