PPT-Variable Scope

Variable variable whos got the variable Copyright 2016 Fred McClurg All Rights Reserved Variable Scope Scope Defined Variable scope has to do with where variables are visible in a program. Name, Scope, and Binding. A name is exactly what you think it is. Usually think of . identifiers but . can be more general. symbols (like . '+' or '_') . can also be names. A binding is an association between two things, such as a name and the thing it names. Chapter 3::. Names, Scopes, and Bindings. Programming Language Pragmatics. Michael L. Scott. We have seen various bindings:. Ruby: type bound to variable during execution. C++ (inheritance) – Variable bound to type at run time. Names. The first step toward wisdom is calling things by their right names.. . Anon. Chinese Proverb. Programming Languages. 2nd edition. Tucker and Noonan. 4.1 Syntactic Issues. 4.2 Variables. Java Unit 7: Loops. A ‘for’ loop is a kind of loop that repeats itself based on an incrementing or decrementing control variable called a ‘loop index’.. It’s the best kind of loop to use when you know in advance how many times the loop should run.. CP212. Winter 2012. Topics. Subroutines. Functions. Modular programming. 3 Main Benefits. Variable and Subroutine Scope. Using and Passing Parameters. Module level "Global" variables. Passing arrays. Scope of a variable. The range of statements in which the variable is visible. A variable is . visible . in a statement if it can be referenced in that statement. A variable is . local . in a program unit (block) if it is declared there. Specifiers. AUTO. Key word auto precedes the normal variable declaration. All local variables are auto by default. Created when function is called and destroyed when function terminates. Life time of function run time. [N. ames. , Bindings, and Scopes]. Dr. Manmath N. Sahoo. Dept. of CSE, NIT Rourkela. Outline. Introduction . Names. Variables. The Concept of Binding. Object Lifetime and Storage Management. Scope . Scope and Lifetime. Example. var. a = 2;. var. b = 2;. console.log(a + b);. Recap of the previous lecture. Scope in ES3 World. The Scope of a . Variable. The scope of a variable are the locations . where it is accessible.. Clique Tree and VE. Probabilistic. Graphical. Models. Inference. Variable Elimination & Clique Trees. Variable elimination. Each step creates a factor . . i. . through factor product. A variable is eliminated in . Name, Scope, and Binding. A name is exactly what you think it is. Usually think of . identifiers but . can be more general. symbols (like . ' ' or '_') . can also be names. A binding is an association between two things, such as a name and the thing it names. Scope and block structure. Declarations. Programming Languages 3 © 2012 David A Watt, University of Glasgow. Bindings and environments . (1). The meaning of an expression/command depends on the declarations of any . Names. Aspect of PL . design. (3.1) How does an object get a name? . Binding time & object life-cycle. (3.2) Where does an object live? . Memory allocation strategies. “Hi, what’s. your name?”. the “state” of the process . the . “state” is the collection of variables and their values. For variables: storage. , binding, . types, scope. Design issues for . identifiers. maximum length for the name? what are the legal characters?.