WEEK 5

EMAIL, AUTHENTICATION, AUTHORIZATION

I GOT 99 PROBLEMS AND

FOR EXPRESSIONS

DIFFERENT LANGUAGES HAVE

TWO KINDS OF SCOPE RULES

CONTEXT DETERMINED BEFORE RUN-TIME

CONTEXT DETERMINED AT RUN-TIME

HAVING BOTH IS WHY RUBY FEELS SO

TO WRITE

WITHOUT RUBY'S SCOPE RULES

(PROBABLY MORE)

I'M GOING TO SPEAK

RAISE YOUR HAND IF YOU HAVE

FIRST SCOPE

UNIQUE RULES

LIKE OTHER LANGUAGES

UNLIKE OTHER LANGUAGES

BEGIN WITH AN

CONTEXT IS BOTH STATIC AND RELATIVE

CONSTANTS ARE EITHER

(ACTIVERECORD::BASE)

OR MODULE

PROMISE!

CURRENT CLASS OR MODULE IS

LET YOU

METHODS HAVE SPECIAL RULES FOR

LEAST ACCESS CONTROL

RECEIVER MUST BE AN INSTANCE OF THE

MOST ACCESS CONTROL

RECEIVER MUST BE THE

PICKY AS F*CK

RECEIVER'S CLASS MUST BE THE SAME AS THE

THIRD SCOPE

VERY DIFFERENT CONCEPT THAN THE

THAT REFERENCES THE CURRECT OBJECT

ALWAYS THE CURRENT OBJECT

FOR METHOD CALLS

2 SIMPLE RULES

FOURTH AND LAST SCOPE FOR TODAY

LOCAL VARIABLES

INSTANCE VARIABLES

CLASS VARIABLE

GLOBAL VARIABLE

CLASS AND GLOBAL VARIABLES ARE

LOCAL AND INSTANCE VARIABLES ARE

SHORT-LIVED REFERENECES TO OBJECTS

ISOLATED TO DECLARATION CONTEXT

DECLARATION MEANS

STORE OBJECT STATE

ALLOWS OBJECTS OF THE SAME CLASS TO HAVE

DECLARED WITHIN

WHEN NECESSARY

OBSERVE AND ALTER WITH

INSTANCES VARIABLES

NO MORE!

IF YOU'RE STILL CONFUSED

RUBY SCOPES ARE

GOING TO TAKE

UNITL YOU

I'LL BE GENTLE, I PROMISE