ELOQUENT JAVASCRIPT

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VALUES, TYPES, AND OPERATORS

- everything inside a computer is data

- data can be read, modified, created

- data is stored as sequences of bits

- bits are two valued things (0 and 1)

- pieces of data are values

- values are created by invoking their names

- values are stored in bindings

- every value has a data type

- values can convert to another data type, either on their own (coercion) or by applying a method

data type: NUMBER

- numeric value

- integer or fractional

- used for artimetic operations: addition, substraction, divisions, multiplication, remainder

- special numbers Infinity, -Infinity, NaN

- NaN is never equal to itself

- null (nothing)

data type: STRING

- text in quotes

- escaping characters: - \\ backslash

- \n new line

- \t tab

- \' single quote

- \" double quote

- concatenation: adding multiple strings into one

- template literals: in backticks

- ${ } inside template literal will compute value, convert it to string and add at that place

data type: BOOLEAN

- true or false

data type: UNDEFINED

- unassigned value

OPERATORS

- unary: - typeof, minus (marking value as negative)

- binary: - arithmetic

- comparison

- logical, except conditional

- ternary: - conditional

PROGRAM STRUCTURE

- expression is a fragment of code, that produces a value

- bindings hold values

- bindings are declared through statements

- program is a list of statements

- statements can be groupped into a single statement using { }

- single let statement may define multiple bindings

- const stands for constant binding

- collection of bindings and their values is enviroment

data type: FUNCTION

- piece of program wrapped in a value

- browsers have some build-in functions

- prompt, alert, confirm, console.log

- calling means executing a function

- functions can produce (return) values or cause side effects

CONTROL FLOW

- statements are executed from top to bottom

- this flow can be changed with conditional statements, switch statement and loop

WHILE LOOP

initialize counter; while (condition) {code; update counter;}

DO.. WHILE LOOP

initialize counter; do {code; update counter;} while (condition);

FOR LOOP

for (initialize counter; condition; update counter) {code}