Typology of Programming Languages E Early Languages E

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Typology of program m ing languages

e Early Languages E

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Early Languages

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The Tower of Babel

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Table of Contents

Fortran

ALGOL

COBOL

The second wave

The finale

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IBM Mathematical Formula Translator system

Fortran I, 1954-1956, IBM 704, a team led by John Backus.

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IBM 704 (1956)

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IBM Mathematical Formula Translator system

The m ain goal is user satisfaction (econom ical interest) rather than academ ic. Com piled language.

a single data structure : arrays com m ents arithm etics expressions DO loops subprogram s and functions I/O m achine independence

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FORTRAN’s success

Because: program m ers productivity easy to learn by IBM the audience was m ainly scientific sim plifications (e.g., I/O)

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FORTRAN I

CC
FIND THE MEAN OF N NUMBERS AND THE NUMBER OF VALUES GREATER THAN IT

DIMENSION A(99) REAL MEAN

READ(1,5)N

FORMAT(I2)

5
READ(1,10)(A(I),I=1,N)

FORMAT(6F10.5)
10

SUM=0.0 DO 15 I=1,N

15
SUM=SUM+A(I)

MEAN=SUM/FLOAT(N)

NUMBER=0

DO 20 I=1,N
IF (A(I) .LE. MEAN) GOTO 20

NUMBER=NUMBER+1
CONTINUE

20 25

WRITE (2,25) MEAN,NUMBER

FORMAT(11H MEAN = ,F10.5,5X,21H NUMBER SUP = ,I5)

STOP

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END

Fortran on Cards

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Fortrans

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Early Languages

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Table of Contents

Fortran

ALGOL

COBOL

The second wave

The finale

Typology of program m ing languages

Early Languages

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ALGOL, Demon Star, Beta Persei, 26 Persei

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ALGOL 58

Originally, IAL, International Algebraic Language.

Usable for algorithm publications in scientific reviews

As close as possible to the usual m athem atical notations

Readable without assistance

Autom atically translatable into m achine code

Meeting between 8 Am ericans and Europeans in Zurich. ALGOL 58.

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ALGOL 58

IAL was considered ”unspeakable and pom pous acronym ”

Introduced the fundam ental notion of com pound statem ent

restricted to control flow only not tied to identifier scope

Used during 1959 for publication Prim ary contribution was to later languages: a basis for JOVIAL ꢀick, MAD, and NELIAC.

Early com prom ise design soon superseded by ALGOL 60

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JOVIAL

”Jules Own Version of the International Algorithm ic Language.”

Developed to write soﬅware for the electronics of m ilitary aircraﬅ by Jules Schwartz in 1959.

Runs the Advanced Cruise Missile, B-52, B-1, and B-2 bom bers, C-130, C-141, and C-17 transport aircraﬅ, F-15, F-16, F-18, and F-117 fighter aircraﬅ, LANTIRN, U-2 aircraﬅ, E-3 Sentry AWACS aircraﬅ, Special Operations Forces, Navy AEGIS cruisers, Arm y Multiple Launch Rocket System (MLRS), Arm y UH-60 Blackhawk helicopters, ..

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ALGOL 60

Figure: John Mac Carthy, Fritz Bauer, Joe Wegstein. Boꢁom row: John Backus, Peter Naur, Alan Perlis

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ALGOL 60: Novelties

Use of BNF to describe the syntax Inform al sem antics Block structure Dynam ic arrays Advanced control flow (if, for…) Recursivity

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ALGOL 60: One syntax, three lexics

Reference language (used in the ALGOL-60 Report)

a[i+1] := (a[i] + pi x r^2) / 6.02₁₀23;

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ALGOL 60: One syntax, three lexics

Reference language (used in the ALGOL-60 Report)

a[i+1] := (a[i] + pi x r^2) / 6.02₁₀23;

Publication language

a_i+1← {a_i+ π × r²}/6.02 × 10²³;

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ALGOL 60: One syntax, three lexics

Reference language (used in the ALGOL-60 Report)

a[i+1] := (a[i] + pi x r^2) / 6.02₁₀23;

Publication language

a_i+1← {a_i+ π × r²}/6.02 × 10²³;

Hardware representations – im plem entation dependent

a[i+1] := (a[i] + pi * r^2) / 6.02E23; or a(/i+1/) := (a(/i/) + pi * r ** 2) / 6,02e23; or A(.I+1.) .= (A(.I.) + PI * R 'POWER' 2) / 6.02'23.,

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COS 301 Programming Languages Evolution of the Major Programming Languages UMaine School of Computing and Information Science COS 301 - 2018 Topics Zuse’s Plankalkül Minimal Hardware Programming: Pseudocodes The IBM 704 and Fortran Functional Programming: LISP ALGOL 60 COBOL BASIC PL/I APL and SNOBOL SIMULA 67 Orthogonal Design: ALGOL 68 UMaine School of Computing and Information Science COS 301 - 2018 Topics (continued) Some Early Descendants of the ALGOLs Prolog Ada Object-Oriented Programming: Smalltalk Combining Imperative and Object-Oriented Features: C++ Imperative-Based Object-Oriented Language: Java Scripting Languages A C-Based Language for the New Millennium: C# Markup/Programming Hybrid Languages UMaine School of Computing and Information Science COS 301 - 2018 Genealogy of Common Languages UMaine School of Computing and Information Science COS 301 - 2018 Alternate View UMaine School of Computing and Information Science COS 301 - 2018 Zuse’s Plankalkül • Designed in 1945 • For computers based on electromechanical relays • Not published until 1972, implemented in 2000 [Rojas et al.] • Advanced data structures: – Two’s complement integers, floating point with hidden bit, arrays, records – Basic data type: arrays, tuples of arrays • Included algorithms for playing chess • Odd: 2D language • Functions, but no recursion • Loops (“while”) and guarded conditionals [Dijkstra, 1975] UMaine School of Computing and Information Science COS 301 - 2018 Plankalkül Syntax • 3 lines for a statement: – Operation – Subscripts – Types • An assignment
ALGOL 60 Programming on the Decsystem 10.Pdf

La Trobe University DEPARTMENT OF MATHEMATICS ALGOL 60 Programming on the DECSystem 10 David Woodhouse Revised, August 1975 MELBOURNE, AUSTRALIA ALGOL 60 Programming on the DECSystem 10 David Woodhouse Revised, August 1975 CE) David Woodhouse National Library of Australia card number and ISBN. ISBN 0 85816 066 8 INTRODUCTION This text is intended as a complete primer on ALGOL 60 programming. It refers specifically to Version 4 of the DECSystem 10 implementation. However, it avoids idiosyncracies as far as possible, and so should be useful in learning the language on other machines. The few features in the DEC ALGOL manual which are not mentioned here should not be needed until the student is sufficiently advanced to be using this text for reference only. Exercises at the end of each chapter illustrate the concepts introduced therein, and full solutions are given. I should like to thank Mrs. K. Martin and Mrs. M. Wallis for their patient and careful typing. D. Woodhouse, February, 1975. CONTENTS Chapter 1 : High-level languages 1 Chapter 2: Languagt! struct.ure c.f ALGOL 6n 3 Chapter 3: Statemp.nts: the se'1tences {'\f the language 11 Chapter 4: 3tandard functions 19 Chapter 5: Input an~ Outp~t 21 Chapter 6: l>rray~ 31 Chapter 7 : For ane! ~hil~ statements 34 Chapter 8: Blocks anr! ',: ock sc rll,~ turr. 38 Chapter 9: PrOCe(:l1-:-~S 42 Chapter 10: Strin2 vp·jaLlps 60 Chapter 11: Own v~rj;lI'.i..es clOd s~itc.hef, 64 Chapter 12: Running ~nd ,;ebllggi"1g 67 Bibliography 70 Solutions to Exercises 71 Appendix 1 : Backus NOlUlaj F\:q'm 86 Appendix 2 : ALGuL-like languages 88 Appenclix 3.