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A Quick Overview of Languages FORTRAN • • • • • • • • • Designed in 1955 First release of the compiler in 1957 Algebraic in nature Scientific (numeric not string oriented) Card format rules Layou … main then subroutines/functions Implicit variable declaration Initially arithmetic if not logical if Labels with goto statement number not end if Lisp • • • • Functional not procedural: also interpreted Simple and concise List processing: atoms and lists Many functions. Two important: car cdr • Notice not easy to read • Author didn’t do the same problem as example • Many features of standard languages hard to find • Loops with recursion , etc. Algol • Number of variations before standardized • Major breakthroughs – – – – block structured value and reference parameters procedures could be recursive dynamic arrays • Not revolutionary but more towards today’s general programming languages Cobol • • • • • Business language Report oriented (compare to previous langs) Rearranging and format oriented. Procedural but barely (no parameters) Four main divisions – identification, environment, data, procedure • Database support PL/1 • Business needed more numerical power • Science needed more sophisticated means of managing volumes of results • PL/1 was to be THE universal language • Introduction of – pointers, exception handling, concurrency Algol 68 and Pascal • PL/1 was not as orthogonal as desired • Algol 68 resolved that but was never widely accepted. • Pascal was a small variant of Algol 60 developed for teaching. It did not contain all features that a professional developer needed. – Passing arrays as parameters awkward.. One size/type only – managing large systems of routines/libraries C • • • • Grew out of UNIX/Bell Labs in 70s Predecessor was used to design UNIX Many who studied UNIX, learned c Language without many constraints – no type check on parameters/addresses • Free distribution with UNIX • For years no standard existed • c++ improvements made it more widely acceptable in 1990 Prolog • • • • Logic programming not procedural Rule based Database flavor AI applications Ada • Move by DOD to minimize the problem of managing all of government code subcontracted in so many different languages • Massive effort. Most thought the government would drive programming in that direction. NOT • Good for exception handling and encapsulation • Limited object-oriented language Smalltalk • “Pure” Object oriented • Basis of comparison for all languages which claim to be object-oriented • Objects passing messages model • includes an environment for development C++ • Object oriented extensions • Cleans up and standardizes c Java • • • • • Platform independent Interpreted by Java virtual machine Web based to spread load to client side Security is important Also runs outside of web – applets in web – applications outside