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In computer programming, ellipsis notation (.. or ...) is used to denote ranges, or an unspecified number of arguments. Most programming languages other than Perl6 require the ellipsis to be written as a series of periods; a single (Unicode) ellipsis character cannot be used. == Ranges == In some programming languages (including Ada, Perl, Ruby, Groovy, Haskell, and Pascal), a shortened two-dot ellipsis is used to represent a range of values given two endpoints; for example, to iterate through a list of integers between 1 and 100 inclusive in Perl: : foreach (1..100)In Ruby the ... operator denotes a half-open range, i.e. that includes the start value but not the end value.In Rust the ... operator denotes an inclusive range for cases in matches and the .. operator represents a range not including the end value.Perl overloads the ".." operator in scalar context as a stateful bistable Boolean test, roughly equivalent to "true while ''x'' but not yet ''y''", similarly to the "," operator in sed and AWK.〔(perlop - perldoc.perl.org )〕 In Perl6, the 3-character ellipsis is also known as the "yadda yadda yadda" operator and, similarly to its linguistic meaning, serves as a "stand-in" for code to be inserted later. In addition, an actual Unicode ellipsis character is used to serve as a type of marker in a perl6 format string.〔(Exegesis 7: Formats - perl6 )〕 The GNU Compiler Collection has an extension to the C and C++ language to allow ''case ranges'' in switch statements: switch(u) Delphi / Turbo Pascal / Free Pascal: var FilteredChars: set of (); var CheckedItems: set of (); In the Unified Modeling Language (UML), a two-character ellipsis is used to indicate variable cardinality of an association. For example, a cardinality of 1.. * means that the number of elements aggregated in an association can range from 1 to infinity (a usage equivalent to Kleene plus). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Ellipsis (computer programming)」の詳細全文を読む スポンサード リンク
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