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I have lots of notes in my local files and also I plan to move them to gists.

// TODO: improve&refactor

// symfony convert request body to array:

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/*
 * searching some values in mysql is not as easy as you think
 * some search may not work way you think
 * for example, it's virtually impossible to search NULL values
 * without `IS NULL`
 *
 * you can test this queries using your local mysql or online services like sqlfiddle
 *
 */

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// special Javascript values
const specials = [null, true, false, undefined, NaN, 1/0, -1/0, -0];

function getMixValue(){
    return randIndex([
            randSpecial,
            randInt,
            randFloat,
            randStr,

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Some notes about conversion to number in javascript

javascript has lots of methods to convert any value to number

• all methods could be divided into 2 groups: string and native methods
  • String methods are parseInt and parseFloat
  • Native mathods are Number and Math methods

all native methods behave the same way, sometimes with additional transform

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some esoteric ES6 functions

var getDiagonalMatrix = N=>Array(N).fill(0).map((x,i)=>Array(N).fill(i).map((x,j)=>i==j?1:0));
var getNDArray = (N, x)=>N.length?(Array(N[0]).fill(0).map(()=>arr(N.slice(1),x))):x;


var toBase =  (x,n,r=[])=>x ? toBase(Math.trunc(x/n), n, [ x%n, ...r]):r;