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19-544: For the Misplaced Pages policy often abbreviated "OR", see Misplaced Pages:No original research . [REDACTED] Look up OR , or , -or , or- , or Or. in Wiktionary, the free dictionary. Or or OR may refer to: Arts and entertainment [ edit ] Film and television [ edit ] "O.R.", a 1974 episode of M*A*S*H Or (My Treasure) ,

38-506: A sequence point : they completely evaluate the first argument, including any side effects , before (optionally) processing the second argument. ALGOL 68 used proceduring to achieve user-defined short-circuit operators and procedures. The use of short-circuit operators has been criticized as problematic: The conditional connectives — " cand " and " cor " for short — are ... less innocent than they might seem at first sight. For instance, cor does not distribute over cand : compare in

57-833: A 2004 movie from Israel ( Or means "light" in Hebrew) Music [ edit ] Or (album) , a 2002 album by Golden Boy with Miss Kittin O*R , the original title of Olivia Rodrigo's album Sour , 2021 "Or", a song by Israeli singer Chen Aharoni in Kdam Eurovision 2011 Or Records , a record label Organized Rhyme , a Canadian hip-hop group featuring Tom Green Businesses and organizations [ edit ] Or (political party) ( lit.   ' light ' ), Israel OR Books , an American publisher Owasco River Railway , Auburn, New York, U.S. (by reporting mark) TUI fly Netherlands , formerly Arke ,

76-794: A Dutch charter airline (by IATA designator) Language and linguistics [ edit ] Or (digraph) , in the Uzbek alphabet Or (letter) (or forfeda ), in Ogham, the Celtic tree alphabet Odia language , a language spoken in East India (ISO 639) Or, an English grammatical conjunction -or, an English agent noun suffix Or, a digraph in Taiwanese's Daī-ghî tōng-iōng pīng-im phonetic transcription Places [ edit ] Europe [ edit ] Or (Crimea) , an isthmus of

95-525: A gold or yellow tincture (from the French word for "gold") Own Recognizance , the basis for releasing someone awaiting trial without bail See also [ edit ] '0r' (zero r), meaning "no roods ", in old measurements of land area And (disambiguation) OAR (disambiguation) Ore (disambiguation) Either/Or (disambiguation) Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with

114-625: A logical operation Bitwise OR , an operator in computer programming, typically notated as or or | The short-circuit operator or , notated or , || , or or else Elvis operator , an operator in computer programming that returns its first operand if its value is considered true, and its right operand if not Null coalescing operator , an operator in computer programming Onion routing , anonymous networking technique (also Onion Router) OR gate , an integrated circuit in electronics Object–relational mapping Other uses in science and technology [ edit ] Odds ratio ,

133-689: A measure of effect size in statistics OR , a previous title of the Journal of the Operational Research Society Operating room , in medicine Operations research , or operational research, in British English Operations readiness Titles and ranks [ edit ] Official receiver , a statutory office holder in England and Wales Order of Roraima of Guyana , an award of

152-401: A succinct conditional construct. Examples include: Perl idioms: POSIX shell idioms: This idiom presumes that echo cannot fail. Despite these benefits, minimal evaluation may cause problems for programmers who do not realize (or forget) it is happening. For example, in the code if myfunc(b) is supposed to perform some required operation regardless of whether do_something()

171-501: Is equivalent to if x then x else y . In either case, x is only evaluated once. The generalized definition above accommodates loosely typed languages that have more than the two truth-values True and False , where short-circuit operators may return the last evaluated subexpression. This is called "last value" in the table below. For a strictly-typed language, the expression is simplified to if x then y else false and if x then true else y respectively for

190-528: Is executed, such as allocating system resources, and expressionA evaluates as false, then myfunc(b) will not execute, which could cause problems. Some programming languages, such as Java , have two operators, one that employs minimal evaluation and one that does not, to avoid this problem. Problems with unperformed side effect statements can be easily solved with proper programming style, i.e., not using side effects in boolean statements, as using values with side effects in evaluations tends to generally make

209-415: Is never called. This is because a != 0 evaluates to false . This feature permits two useful programming constructs. Both are illustrated in the following C snippet where minimal evaluation prevents both null pointer dereference and excess memory fetches: Since minimal evaluation is part of an operator's semantic definition and not an optional optimization , a number of coding idioms rely on it as

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228-468: Is that non-short-circuiting operators can be defined out of short-circuit logic to have the same sequence of evaluation. As you look at the table below, keep in mind that bitwise operators often do not behave exactly like logical operators, even if both arguments are of 0 , 1 or Boolean type. Examples: Usual example, using a C-based language: Consider the following example: In this example, short-circuit evaluation guarantees that myfunc(b)

247-600: The Black Sea Or (river) , a tributary of the Ural Province of Oristano , Italy (by vehicle code) United States [ edit ] Oregon , a U.S. state (by postal abbreviation) Orange Line (Washington Metro) India [ edit ] Odisha formerly Orissa, a state of India Science, technology, and mathematics [ edit ] Computing and mathematics [ edit ] Or (logic) , logical disjunction Exclusive or (XOR),

266-607: The Republic of Guyana Other ranks , personnel who are not commissioned officers, usually including non-commissioned officers (NCOs), in militaries of many Commonwealth countries Other uses [ edit ] Or (name) , Hebrew given name and surname Official Records of the American Civil War Olympic record , a term for the best performances in Olympic Games Or (heraldry) ,

285-520: The boolean case. Although AND takes precedence over OR in many languages, this is not a universal property of short-circuit evaluation. An example of the two operators taking the same precedence and being left-associative with each other is POSIX shell 's command-list syntax. The following simple left-to-right evaluator enforces a precedence of AND over OR by a continue : Short-circuit logic, with or without side-effects, have been formalized based on Hoare's conditional . A result

304-413: The case ¬A ∧ C , the second expression requires B to be defined, the first one does not. Because the conditional connectives thus complicate the formal reasoning about programs, they are better avoided. In any programming language that implements short-circuit evaluation, the expression x and y is equivalent to the conditional expression if x then y else x , and the expression x or y

323-422: The code opaque and error-prone. Short-circuiting can lead to errors in branch prediction on modern central processing units (CPUs), and dramatically reduce performance. A notable example is highly optimized ray with axis aligned box intersection code in ray tracing . Some compilers can detect such cases and emit faster code, but programming language semantics may constrain such optimizations. An example of

342-724: The title Or . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Or&oldid=1250179930 " Categories : Disambiguation pages Place name disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages OR">OR The requested page title contains unsupported characters : ">". Return to Main Page . Short-circuit operator In programming languages with lazy evaluation ( Lisp , Perl , Haskell ),

361-556: The usual Boolean operators short-circuit. In others ( Ada , Java , Delphi ), both short-circuit and standard Boolean operators are available. For some Boolean operations, like exclusive or (XOR), it is impossible to short-circuit, because both operands are always needed to determine a result. Short-circuit operators are, in effect, control structures rather than simple arithmetic operators, as they are not strict . In imperative language terms (notably C and C++ ), where side effects are important, short-circuit operators introduce

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