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OBJECTS

README.md

I/O

alert(string) : browser alert msg

CONVERSION

int parseInt(str) : str to int
int parseInt(str, int radix) : str to int, in base radix

Array

ARRAY.PROP :

length :
bool every(function) : return true if each value evaluates function to true;
filter(function) : keep elements such that function(x) = true;
forEach(function) : applies function to each element;
from(arr) : copy an array-like/iterable

  • note: shallow copy

join(sep) : join using sep
indexOf(item) : index of item
array map(function) : return a copy with function(x) for each x;
type pop() : remove and return last
undefined .push(VAL) : append to end
reduce(function) : apply function on each element, passing result of previous iteration;
type .shift() : remove and return first
array slice(start, end) : return from start to end (excluded)
bool some(function) : true if at least one value evaluates function to true;
sort(function) : sort using function;

  • function(a,b) : returns 0 if equal, a negative value if first args less than second, otherwise positive

splice(pos, n, subst) : remove n elements at pos, add subst’ elements at pos
undefined unshift(VAL) : append to start

Object

prototype : access element of class;

  • can add/ change class (prototype) parameters
  • e.g. CLASS_NAME.prototype.PARAMETER

freeze(“VAR”) : make object VAR immutable
fromEntries(ARR) : object from array of arrays, each containing the pair of key and val (val optional)
hasOwnProperty(str): boolean : if obj has property named str

static

entries(obj): array : object to array of pairs <key, val>

EVENT

event.* : event object properties (in event handlers)

currentTarget : (some difference from target)
target : "calling element", as object (containing html attributes as fields)

  • e.g.: event.target.value : value attribute of calling html tag

HTTP

fetch('URL', init?) -> Promise : http request

  • e.g.: init={method = GET} : http method
    • response fields:
    • ok:boolean : true if in [200;400[

REGEX / MATCHING

str str.match(regex) : try to match, and return list of matched part(s) of string,
* or null if not matched
str.replace(regex1, str2) : replace regex1 matched part in str with str 2;
* you can use, in str2, $n for indicating n-th element found

bool regex.test(str) : test (match) a regex on a string, return bool

STRING

.length :

indexof(char) :
.join(sep) :
.log(ARG1, …) : print args to console
.prototype.trim() : remove start/end whitespaces
split() :
.substring(start, end) :
.substr(start, length) :

Date :
// day=1..31, month=0..11

Date() :
Date(string) :
Date(y, m, d) :

Date object :
getDay() :
toLocaleString("locales":string, {formats}?) : convert to locales time, use optional formats (types)

  • e.g.: formats={year:"numeric",month:"short"}

toLocaleDateString(..) : just like toLocaleString(), only using date and not time

toDateString() :

Error

message : error msg

DOM

document

The HTML DOM Document Object is the owner of all other objects in your web page.
document : the object of the following attrs/methods

Finding HTML Elements

getElementById(ID) :
getElementsByClassName(NAME) :
getElementsByTagName(NAME) :

Adding and Deleting Elements

appendChild(ELEM) :
createElement(ELEM) : create an HTML element
removeChild(ELEM) :
replaceChild(NEW, OLD) :
write(TEXT) : Write into an HTML output stream opened with open

Adding Events Handlers

getElementById(id).onclick = function(){code} : Adding event handler code to an onclick event

Finding HTML Objects

anchors : Returns all <a> elements that have a name attribute
applets : Deprecated
baseURI : Returns the absolute base URI of the document
body : Returns the <body> element
cookie : Returns the document's cookie
doctype : Returns the document's doctype
documentElement : Returns the <html> element
documentMode : Returns the mode used by the browser
documentURI : Returns the URI of the document
domain : Returns the domain name of the document server
domConfig : Obsolete
embeds : Returns all <embed> elements
forms : Returns all <form> elements
head : Returns the <head> element
images : Returns all <img> elements
implementation : Returns the DOM implementation
inputEncoding : Returns the document's encoding (character set)
lastModified : Returns the date and time the document was updated
links : Returns all <area> and <a> elements that have a href attribute
readyState : Returns the (loading) status of the document
referrer : Returns the URI of the referrer (the linking document)
scripts : Returns all <script> elements
strictErrorChecking : Returns if error checking is enforced
title : Returns the <title> element
URL : Returns the complete URL of the document

element

element :

Changing HTML Elements

attribute = new value : Change the attribute value of an HTML element
innerHTML = new html content : Change the inner HTML of an element
outerHTML = new html content : Change the outer HTML of an element
setAttribute(attribute, value) : Change the attribute value of an HTML element
style.property = new style : Change the style of an HTML element

OTHER MODULES

Json

JSON.* :

string .stringify(obj) : object to json string
string .stringify(obj, arg, n) : with prettify, insert newline, using n lines
object .parse(str) : string to json

Math

Math.* :

PI :

abs() :
cos() :
float floor() :
float max(...args) : max arg
float random() : [0,1] , 0 included, 1 excluded
sin() :
sqrt() :

?

obj.review(str) : ?
obj.newProp(str) : ?