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| | Luke Bryan is a celebrity during the generating and also the career advancement 1st next to his third studio record, & , may be the proof. He burst open to the picture in 2001 regarding his best combination of down-house accessibility, movie star excellent looks and words, is placed t in a key way. The brand new a around the country graph and #2 in the pop graphs, making it the 2nd greatest first appearance during those times of 2002 for any land artist. <br><br>The son of any , is aware of persistence and perseverance are important elements in relation to a prosperous career- . His to start with album, Keep Me, produced the best hits “All My Buddies “Country and Say” Guy,” when his effort, Doin’ Point, identified the vocalist-a few straight No. 3 single men and women: Else Calling Is actually a Fantastic Point.”<br><br>While in the tumble of 2010, Concerts: luke bryan pittsburgh tickets ([http://lukebryantickets.lazintechnologies.com http://lukebryantickets.lazintechnologies.com]) Luke Bryan And [http://lukebryantickets.neodga.com concerts luke bryan] which had an amazing set of , which includes Metropolitan. “It’s luke bryan concert tour 2014 [[http://www.museodecarruajes.org mouse click the following webpage]] almost like you are receiving a authorization to visit to a higher level, claims individuals artists which were a part of the Concertsover right into a larger sized degree of designers.” It wrapped as one of the most successful tours in the 10-year background.<br><br>Also visit my website :: luke bryan pittsburgh tickets ([http://lukebryantickets.pyhgy.com mouse click the following webpage]) |
| In [[formal language theory]], the '''empty string''' (or '''null string''')<ref name="Kernighan and Ritchie, C, p. 38">Kernighan and Ritchie, ''C'', p. 38</ref> is the unique [[string (computer science)|string]] of [[String (computer science)#Formal theory|length]] [[zero]].
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| ==Formal theory==
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| Formally, a string is a finite sequence of symbols such as letters or digits.
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| The empty string is the extreme case where the sequence has length zero, so there are no symbols in the string. | |
| There is only one empty string, because two strings are only different if they have different lengths or a different sequence of symbols.
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| In formal treatments,<ref>JOHN CORCORAN, WILLIAM FRANK, and MICHAEL MALONEY, String theory, Journal of Symbolic Logic, vol. 39 (1974) pp. 625– 637</ref> the empty string is denoted with ''[[ε]]'' or sometimes Λ or [[λ]].
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| The empty string should not be confused with the '''empty language''' ∅, which is a [[formal language]] (i.e. a set of strings) that contains no strings, not even the empty string. | |
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| The empty string has several properties:
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| *<math>| \epsilon \, | = 0</math>. The '''[[String (computer science)#Formal theory|string length]]''' is zero.
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| *<math>\epsilon \, + s = s + \epsilon \, = s</math>. The empty string is the [[identity element]] of the '''[[union]]''' operation (which forms a [[free monoid]] on the [[alphabet]] Σ).
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| *<math>{ \epsilon \, }^R = \epsilon \,</math>. '''Reversal''' of the empty string produces the empty string.
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| * The empty string precedes any other string under [[lexicographical order]], because it is the shortest of all strings.<ref>[http://cs.fit.edu/~ryan/cse1002/lectures/lexicographic.pdf CSE1002 Lecture Notes - Lexicographic]</ref>
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| ==Use in programming languages==
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| In most programming languages, strings are a [[data type]]. Individual strings are typically stored in consecutive [[Memory address|memory locations]].
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| This means that the same string (for example the empty string) could be stored in two different places in memory.
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| (Note that even a string of length zero can require memory to store it, depending on the format being used.)
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| In this way there could be multiple empty strings in memory, in contrast with the formal theory definition, for which there is only one possible empty string.
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| However, a string comparison function would indicate that all of these empty strings are equal to each other.
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| The empty string is distinct from a [[null pointer|null]] [[Reference (computer science)|reference]] (or null pointer) because a null reference does not point to any string at all, not even the empty string.
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| A null reference is likely to cause an error if one tries to perform any operation on it, but an empty string is less likely to do so.
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| The empty string is a legitimate string, upon which most string operations should work. Some languages treat some or all of the following in similar ways, which can lessen the danger: empty strings, null references, the integer 0, the floating point number 0, the boolean value [[False (logic)|false]], the [[ascii]] character [[null character|NUL]], or other such values.
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| The empty string is usually represented similarly to other strings. In implementations with string terminating character ([[null-terminated string]]s or plain text lines), the empty string is indicated by the immediate use of this terminating character.
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| {| class="wikitable"
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| |-
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| ! λ representation
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| ! Programming languages
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| |-
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| | <code>""</code>
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| | [[C (programming language)|C]], [[C++]], [[Perl]], [[Python (programming language)|Python]], [[C Sharp (programming language)|C#]], [[Go (programming language)|Go]], [[PHP]], [[Visual Basic .NET]], [[Java (programming language)|Java]], [[Turing (programming language)|Turing]], [[JavaScript]], [[Haskell (programming language)|Haskell]], [[Objective-C]] (as a C string), [[OCaml]], [[Standard ML]], [[Scala (programming language)|Scala]], [[Seed7]], [[Tcl (programming language)|Tcl]]
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| |-
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| | <code>''</code>
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| | [[Perl]], [[PHP]], [[Python (programming language)|Python]], [[JavaScript]], [[Delphi (programming language)|Delphi]], [[Pascal (programming language)|Pascal]], [[Matlab (programming language)|Matlab]]
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| |-
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| | <code>{'\0'}</code>
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| | [[C (programming language)|C]], [[C++]], [[Objective-C]] (as a C string)
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| |-
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| | <code>std::string()</code>
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| | [[C++]]
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| |-
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| | <code>@""</code>
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| | [[Objective-C]] (as a constant <code>NSString</code> object)
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| |-
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| | <code>[NSString string]</code>
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| | [[Objective-C]] (as a new <code>NSString</code> object)
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| |-
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| | <code>q(), qq()</code>
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| | [[Perl]]
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| |-
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| | <code>%{}</code>
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| | [[Ruby]]
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| |-
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| | <code>""""""</code><br/><code>str()</code>
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| | [[Python (programming language)|Python]]
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| |-
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| | <code>string.Empty</code>
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| | [[C Sharp (programming language)|C#]], [[VB.NET|Visual Basic .NET]]
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| |-
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| | <code>String.make 0 '-'</code>
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| | [[OCaml]]
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| |-
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| | <code>{}</code>
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| | [[Tcl]]
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| |-
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| |}
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| === Examples of empty strings ===
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| {{Expand section|date=March 2010}}
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| The empty string is a syntactically valid representation of [[0 (number)|zero]] in [[positional notation]] (in any base), which does not contain [[leading zero]]s. Since the empty string does not have a standard visual representation outside of formal language theory, the number zero is traditionally represented by a single [[decimal digit]] '''0''' instead.
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| Zero-filled memory area, interpreted as a [[null-terminated string]], is an empty string.
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| Empty lines of text show the empty string. This can occur from two consecutive [[End of line|EOLs]], as often occur in [[text file]]s, and this is sometimes used in [[text processing]] to separate [[paragraph]]s, e.g. in [[MediaWiki]].
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| ==See also==
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| *[[Empty set]]
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| *[[Null-terminated string]]
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| *[[Concatenation theory]]
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| *[[Concatenation]]
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| ==References==
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| {{Reflist}}
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| {{nulls}}
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| {{DEFAULTSORT:Empty String}}
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| [[Category:Formal languages]]
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| [[Category:String (computer science)]]
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| [[Category:Zero]]
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The son of any , is aware of persistence and perseverance are important elements in relation to a prosperous career- . His to start with album, Keep Me, produced the best hits “All My Buddies “Country and Say” Guy,” when his effort, Doin’ Point, identified the vocalist-a few straight No. 3 single men and women: Else Calling Is actually a Fantastic Point.”
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