Topic: simple loop

topics > computer science > programming > program control > Group: repetitive control

generalized repetition


All programming systems need some way to repeatedly execute or process a statement. This is true in data flow languages, control files, 'von Neumann' machines, format lists, Kleene stars, tail recursion, and string processors. Simple loops are loops with a single exit condition. Popular forms are 'repeat ... end_repeat', 'while B do ...', and 'do ... until B'. (cbb 5/80)
Subtopic: loop up

QuoteRef: hehnEC_1977 ;;203 "Finally the notation may be used to abbreviate a recursively defined group." [as condition: action, group- reference.
QuoteRef: schoDV9_1966 ;;7 uses branch pred. (0)....(1)... as case and loop until as repeat
QuoteRef: sammJE_1969 ;;460 loop control by While loop-while-true statement
QuoteRef: kosiPR9_1973 ;;94 LOOP (used a lot) data passed from initial path to output path, on control signal saves and returns done, on feedback input saves and returns done, on output done gives feedback if control was true else passes done to initial path
Quote: replaced ALGOL 60's for statement with while statements and for loops over an arithmetic progression; was too complex [»wirtN6_1966]

Subtopic: functional repetition up

QuoteRef: wessBD_1965 ;; :(func args) test again while ::(func, args) done
QuoteRef: wileDS11_1973 ;;35 repetition by Kleene star * i.e., x*== terminated implicitly or by escape operator
QuoteRef: wileDS11_1973 ;;42 s while f:: s.(f exs *)
QuoteRef: storEF_1970 ;;25 *procedure-call is repeat till true while *-pro is repeat till false

Subtopic: repeat loop up

QuoteRef: stepPD8_1974 ;;217 CYCLE ... REPEAT for DO BEGIN... END

Subtopic: repeat count loop up

Quote: repeat a program by specifying an integer repetition factor; use 0/1 for conditionals [»woolJD_1973]
Quote: need a 'repeat Count' loop construct to avoid declaring dummy control variables [»celkJ7_1981]

Subtopic: loop bound up

Quote: hard real-time requires constant-bounded loops per task activation; allows schedulability analysis [»stoyAD7_1993]
Quote: requiring a loop bound caught many design errors and was practical [»andeT_1985]
Quote: eliminate proofs of termination by avoiding loop forever constructs [»andeT_1985]

Related Topics up

Topic: generalized repetition
(16 items)

Updated barberCB 1/04
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