https://www2.southeastern.edu/Academics/Faculty/kyang/2017/Fall/CMPS401/ClassNotes/CMPS401ClassNotesChap05.pdf
Topics. Binding. Lifetime. Scope. Constants. 3. Chapter 5: Variables. Variables: attributes Example: bind a C static variable to a memory.
To design a type must consider scope
To design a type must consider scope
To design a type must consider scope
Variables. • The Concept of Binding. • Scope. • Scope and Lifetime Load time -- bind a C or C++ static variable to a memory cell).
http://www.nyu.edu/classes/jcf/g22.2110-001_sp11/slides/session2/ImperativeLanguages-NamesScopingAndBindings.pdf
Source: http://www.codingunit.com/c-tutorial-structures-unions-typedef Scope and storage classes ... Can we declare static variables in main()?.
https://web.cs.hacettepe.edu.tr/~bbm301/lectures/lecture5_names.pdf
Scope and Lifetime • In C and C++ a variable is declared in a function using the specifier static – The scope is static and local to the function – The lifetime extends over the entire execution of the program of which it is a part • Static scope is a textual and spatial concept while lifetime is a temporal concept
14 1 6 Static Variables As we have seen external variables have global scope across the entire program (provided extern declarationsare used is files other than where the variable is defined) and a lifetime over the the entire program run
Scopeofavariableistherangeofprogram variableisknown Canbestaticordynamic StaticScoping Usedbymostlanguages(e g PascalModula-2C ) Scopeisassociatedwiththestatictextoftheprogram Candeterminescopebylookingatstructureofprogram Mayhaveholesinscopeofvariable program varM:integer; A procedurevarM:array[1 10]ofreal;(*hidesMinprogram*)
- Once the lifetime of a variable ends the value the variable held is lost Even if the variable is recreated it may be bound to a different memory location • Ways to modify the lifetime/scope of variables - static: a static variable’s lifetime is the entire duration of the program execution
Scope and Lifetime •In C and C++ a variable is declared in a function using the specifier static •The scope is static and local to the function •The lifetime extends over the entire execution of the program of which it is a part •Static scope is a textual and spatial concept while lifetime is a temporal concept 12
with static (lexical) scope rules a scope is defined in terms of the physical (lexical) structure of the program the determination of scopes can be made by the compiler all bindings for identifiers can be resolved by examining the program typically we choose the most recent active binding made at compile time