| Perbandingan -- programming languages (string functions)String functions are used in computer programming languages to manipulate a string or query information about a string (some do both). Most programming languages that have a string datatype will have some string functions although there may be other low-level ways within each language to handle strings directly. In object-oriented languages, string functions are often implemented as properties and methods of string objects. In functional and list-based languages a string is represented as a list (of character codes), therefore all list-manipulation procedures could be considered string functions. However such languages may implement a subset of explicit string-specific functions as well. The most basic example of a string function is the length(string) function. This function returns the length of a string literal. - e.g. length("hello world") would return 11.
Other languages may have string functions with similar or exactly the same syntax or parameters or outcomes. For example in many languages the length function is usually represented as len(string). The below list of common functions aims to help limit this confusion. Common string functions (multi language reference)String functions common to many languages are listed below, including the different names used. The below list of common functions aims to help programmers find the equivalent function in a language. Note, string concatenation and regular expressions are handled in separate pages. Statements in guillemets (« … ») are optional. CharAtDefinition | charAt(string,integer) returns character. | Description | Returns character at index in the string. | Equivalent | See substring of length 1 character. |
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string[i] | ALGOL 68, Pascal, Object Pascal (Delphi), Seed7 | 1 | string[i] | C, C++, C#, D, FreeBASIC, Go, Python1, PHP, Ruby1, Windows PowerShell, JavaScript | 0 | string{i} | PHP (deprecated in 5.3) | 0 | string(i) | Ada | ≥1 | Mid(string,i,1) | VB | 1 | MID$(string,i,1) | BASIC | 1 | string.Chars(i) | VB.NET | 0 | string(i:i) | Fortran | 1 | string.charAt(i) | Java, JavaScript | 0 | string.[i] | OCaml, F# | 0 | String.sub (string, i) | Standard ML | 0 | string !! i | Haskell | 0 | (string-ref string i) | Scheme | 0 | (char string i) | Common Lisp | 0 | (elt string i) | ISLISP | 0 | (get string i) | Clojure | 0 | substr(string, i, 1) | Perl1 | 0 | substr(string, i, 1) | PL/I | 1 | string.at(i) | C++ (std::string only) (w/ bounds checking) | 0 | lists:nth(i, string) | Erlang | 1 | [string characterAtIndex:i] | Objective-C (NSString * only) | 0 | string.sub(string, i, i) (string):sub(i, i) | Lua1 | 1 | string at: i | Smalltalk (w/ bounds checking) | 1 | string index string i | Tcl | 0 | StringTake[string, {i}] | Mathematica1 | 1 | string@i | Eiffel | 1 |
- In this language, the index can be negative, which then indicates the number of places before the end of the string.
{ Example in Pascal }var MyStr: string = 'Hello, World'; MyChar: Char;begin MyChar := MyStr[2]; // 'e' # Example in ALGOL 68 #"Hello, World"[2]; // 'e' // Example in C#"Hello, World"[2]; // 'l' # Examples in Python"Hello, World"[2] # 'l'"Hello, World"[-3] # 'r' ' Example in Visual BasicMid("Hello, World",2,1) ' Example in Visual Basic .NET"Hello, World".Chars(2) ' "l"c " Example in Smalltalk"'Hello, World' at: 2. "$e" Compare (integer result)Definition | compare(string1,string2) returns integer. | Description | Compares two strings to each other. If they are equivalent, a zero is returned. Otherwise, most of these routines will return a positive or negative result corresponding to whether string1 is lexicographically greater than, or less than, respectively, than string2. The exceptions are the Scheme and REXX routines which return the index of the first mismatch. |
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IF string1<string2 THEN -1 ELSE ABS (string1>string2) FI | ALGOL 68 | cmp(string1, string2) | Python (before 3.0 only) | (string1 > string2) - (string1 < string2) | Python (since 3.0) | strcmp(string1, string2) | C, C++ (char * only), PHP | std.string.cmp(string1, string2) | D | StrComp(string1, string2) | VB, Object Pascal (Delphi) | string1 cmp string2 | Perl | string1 <=> string2 | Ruby | string1.compare(string2) | C++ (std::string only) | compare(string1, string2) | REXX, Seed7 | CompareStr(string1, string2) | Pascal, Object Pascal (Delphi) | string1.compareTo(string2) | Java | string1.CompareTo(string2) | VB .NET, C#, F# | (= string1 string2) | Clojure | (string= string1 string2) | Common Lisp | (string-compare string1 string2 p< p= p>) | Scheme (SRFI 13) | (string= string1 string2) | ISLISP | compare string1 string2 | OCaml | String.compare (string1, string2) | Standard ML (returns LESS, EQUAL, or GREATER) | compare string1 string2 | Haskell (returns LT, EQ, or GT) | [string]::Compare(string1, string2) | Windows PowerShell | [string1 compare:string2] | Objective-C (NSString * only) | LLT(string1,string2) LLE(string1,string2) LGT(string1,string2) LGE(string1,string2) | Fortran (returns .TRUE. or .FALSE. ). These functions are based on the ASCII collating sequence. | string1.localeCompare(string2) | JavaScript | bytes.Compare([]byte(string1), []byte(string2)) | Go | string compare ?-nocase? ?-length int? string1 string2 | Tcl | compare(string1,string2,count) | PL/I1 |
1IBM extension. # Example in Pythoncmp("hello", "world") # returns -1 /** Example in REXX */ compare("hello", "world") /* returns index of mismatch: 1 */ ; Example in Scheme(use-modules (srfi srfi-13)); returns index of mismatch: 0(string-compare "hello" "world" values values values) Compare (relational operator-based, Boolean result)Definition | string1 op string2 OR (compare string1 string2) returns Boolean. | Description | Lexicographically compares two strings using a relational operator or function. Boolean result returned. |
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string1 op string2, where op can be any of =, <>, <, >, <= and >= | Pascal, Object Pascal (Delphi), OCaml, Seed7, Standard ML, BASIC, VB, VB .NET, F# | string1 op string2, where op can be any of =, /=, ≠, <, >, <=, ≤ and ≥; Also: EQ, NE, LT, LE, GE and GT | ALGOL 68 | (stringX? string1 string2), where X can be any of =, -ci=, <, -ci<, >, -ci>, <=, -ci<=, >= and -ci>= (operators starting with '-ci' are case-insensitive) | Scheme | (stringX string1 string2), where X can be any of =, -ci=, <>, -ci<>, <, -ci<, >, -ci>, <=, -ci<=, >= and -ci>= (operators starting with '-ci' are case-insensitive) | Scheme (SRFI 13) | (stringX string1 string2), where X can be any of =, -equal, /=, -not-equal, <, -lessp, >, -greaterp, <=, -not-greaterp, >= and -not-lessp (the verbal operators are case-insensitive) | Common Lisp | (stringX string1 string2), where X can be any of =, /=, <, >, <=, and >= | ISLISP | string1 op string2, where op can be any of =, \=, <, >, <= and >= | REXX | string1 op string2, where op can be any of =, ¬=, <, >, <=, >=, ¬< and ¬> | PL/I | string1 op string2, where op can be any of =, /=, <, >, <= and >= | Ada | string1 op string2, where op can be any of ==, /=, <, >, =< and >= | Erlang | string1 op string2, where op can be any of ==, /=, <, >, <= and >= | Haskell | string1 op string2, where op can be any of eq, ne, lt, gt, le and ge | Perl | string1 op string2, where op can be any of ==, !=, <, >, <= and >= | C++ (std::string only), C#, D, Go, JavaScript, Python, PHP, Ruby | string1 op string2, where op can be any of -eq, -ceq, -ne, -cne, -lt, -clt, -gt, -cgt, -le, -cle, -ge, and -cge (operators starting with 'c' are case-sensitive) | Windows PowerShell | string1 op string2, where op can be any of ==, ~=, <, >, <= and >= | Lua | string1 op string2, where op can be any of =, ~=, <, >, <= and >= | Smalltalk | string1 op string2, where op can be any of ==, /=, <, >, <= and >=; Also: .EQ., .NE., .LT., .LE., .GT. and .GE. | Fortran. The operators use the compiler's default collating sequence. |
% Example in Erlang"hello" > "world". % returns false # Example in Windows PowerShell"hello" -gt "world" # returns false ; Example in common lisp(string> "art" "painting") ; returns nil(string< "art" "painting") ; returns non nil ConcatenationMain article: ConcatenationDefinition | concatenate(string1,string2) returns string. | Description | Concatenates (joins) two strings to each other, returning the combined string. Note that some languages like C have mutable strings, so really the second string is being appended to the first string and the mutated string is returned. |
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string1 & string2 | Ada, FreeBASIC, Seed7, BASIC, VB, VB .NET | strcat(string1, string2) | C, C++ (char * only; modifies string1, which must have enough space to store the result) | string1 . string2 | Perl, PHP | string1 + string2 | ALGOL 68, C++ (std::string only), C#, FreeBASIC, Go, Pascal, Object Pascal (Delphi), Java, JavaScript, Windows PowerShell, Python, Ruby, F#, Turing, VB | string1 ~ string2 | D | (string-append string1 string2) | Scheme | (concatenate 'string string1 string2) | Common Lisp | (string-append string1 string2) | ISLISP | (str string1 string2) | Clojure | string1 || string2 | REXX, SQL, PL/I | string1 // string2 | Fortran | string1 ++ string2 | Erlang, Haskell | string1 ^ string2 | OCaml, Standard ML, F# | [string1 stringByAppendingString:string2] | Objective-C (NSString * only) | string1 .. string2 | Lua | string1, string2 | Smalltalk | string1 string2 | SNOBOL | string1 <> string2 | Mathematica |
{ Example in Pascal }'abc' + 'def'; // returns "abcdef" // Example in C#"abc" + "def"; // returns "abcdef" ' Example in Visual Basic"abc" & "def" ' returns "abcdef""abc" + "def" ' returns "abcdef""abc" & Null ' returns "abc""abc" + Null ' returns Null // Example in D"abc" ~ "def"; // returns "abcdef" ; Example in common lisp(concatenate 'string "abc " "def " "ghi") ; returns "abc def ghi" ContainsDefinition | contains(string,substring) returns boolean | Description | Returns whether string contains substring as a substring. This is equivalent to using #Find and then detecting that it does not result in the failure condition listed in the third column of the #Find section. However, some languages have a simpler way of expressing this test. | Related |
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string_in_string(string, loc int, substring) | ALGOL 68 | ContainsStr(string, substring) | Object Pascal (Delphi) | string.Contains(substring) | C#, VB .NET, Windows PowerShell, F# | string.contains(substring) | Java (1.5+) | string.indexOf(substring) >= 0 | JavaScript | strpos(string, substring) !== false | PHP | substring in string | Python (2.3+) | string.find(string, substring) ~= nil | Lua | string.include?(substring) | Ruby | Data.List.isInfixOf substring string | Haskell (GHC 6.6+) | string includesSubString: substring | Smalltalk (Squeak, Pharo) | String.isSubstring substring string | Standard ML | (search substring string) | Common Lisp | ? | ISLISP | (substring? substring string) | Clojure | ! StringFreeQ[string, substring] | Mathematica | index(string, substring, startpos)>0 | PL/I1 |
1startpos is IBM extension. ¢ Example in ALGOL 68 ¢string in string("e", loc int, "Hello mate"); ¢ returns true ¢string in string("z", loc int, "word"); ¢ returns false ¢ // Example In C#"Hello mate".Contains("e"); // returns true"word".Contains("z"); // returns false # Example in Python"e" in "Hello mate" # returns true"z" in "word" # returns false EqualityTests if two strings are equal. See also #Compare and #Compare. Note that doing equality checks via a generic Compare with integer result is not only confusing for the programmer but is often a significantly more expensive operation; this is especially true when using "C-strings". |
string1 == string2 | Python, C++(std::string only), C# Go, JavaScript (similarity), PHP (similarity), Ruby, Erlang, Haskell, Lua, D, Mathematica | string1 === string2 | JavaScript, PHP | string1 == string2 or string1 .EQ. string2 | Fortran | strcmp(string1, string2) == 0 | C, C++ (char * only) | (string=? string1 string2) | Scheme | (string= string1 string2) | Common Lisp, ISLISP | string1 = string2 | ALGOL 68, Ada, Object Pascal (Delphi), OCaml, Pascal, REXX, Seed7, Standard ML, BASIC, VB, VB .NET, F#, Smalltalk, PL/I | test string1 = string2, or [ string1 = string2 ] | Bourne Shell | string1 eq string2 | Perl | string1.equals(string2) | Java | string1 -eq string2, or [string]::Equals(string1, string2) | Windows PowerShell | [string1 isEqualToString:string2], or [string1 isEqual:string2] | Objective-C (NSString * only) |
// Example in C#"hello" == "world" // returns false ' Example in Visual Basic"hello" = "world" ' returns false # Example in Windows PowerShell"hello" -eq "world" # returns false FindDefinition | find(string,substring) returns integer | Description | Returns the position of the start of the first occurrence of substring in string. If the substring is not found most of these routines return an invalid index value – -1 where indexes are 0-based, 0 where they are 1-based – or some value to be interpreted as Boolean FALSE. | Related | instrrev |
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string in string(substring, pos, string[startpos:]) | ALGOL 68 | returns BOOL: TRUE or FALSE, and position in REF INT pos. | InStr(«startpos,»string,substring) | VB (positions start at 1) | returns 0 | INSTR$(string,substring) | BASIC (positions start at 1) | returns 0 | index(string,substring) | AWK | returns 0 | index(string,substring«,startpos») | Perl | returns -1 | instr(«startpos,»string,substring) | FreeBASIC | returns 0 | strpos(string,substring«,startpos») | PHP | returns FALSE | locate(string, substring) | Ingres | returns string length + 1 | strstr(string, substring) | C, C++ (char * only, returns pointer to first character) | returns NULL | std.string.find(string, substring) | D | returns -1 | pos(string, substring«, startpos») | Seed7 | returns 0 | strings.Index(string, substring) | Go | returns -1 | pos(substring, string) | Pascal, Object Pascal (Delphi) | returns 0 | pos(substring, string«,startpos») | REXX | returns 0 | string.find(substring«,startpos») | C++ (std::string only) | returns std::string::npos | string.find(substring«,startpos«,endpos»») | Python | returns -1 | string.index(substring«,startpos«,endpos»») | raises ValueError | string.index(substring«,startpos») | Ruby | returns nil | string.indexOf(substring«,startpos») | Java, JavaScript | returns -1 | string.IndexOf(substring«,startpos«, charcount»») | VB .NET, C#, Windows PowerShell, F# | returns -1 | string:str(string, substring) | Erlang | returns 0 | (string-contains string substring) | Scheme (SRFI 13) | returns #f | (search substring string) | Common Lisp | returns NIL | (string-index substring string) | ISLISP | returns nil | List.findIndex (List.isPrefixOf substring) (List.tails string) | Haskell (returns Just index) | returns Nothing | Str.search_forward (Str.regexp_string substring) string 0 | OCaml | raises Not_found | Substring.size (#1 (Substring.position substring (Substring.full string))) | Standard ML | returns string length | [string rangeOfString:substring].location | Objective-C (NSString * only) | returns NSNotFound | string.find(string, substring) (string):find(substring) | Lua | returns nil | string indexOfSubCollection: substring startingAt: startpos ifAbsent: aBlock string findString: substring startingAt: startpos | Smalltalk (Squeak, Pharo) | evaluate aBlock which is a block closure (or any object understanding value) returns 0 | startpos = INDEX(string, substring «,back» «, kind») | Fortran | returns 0 if substring is not in string; returns LEN(string)+1 if substring is empty | POSITION(substring IN string) | SQL | returns 0 (positions start at 1) | index(string, substring, startpos ) | PL/I1 | returns 0 (positions start at 1) |
1startpos is IBM extension. ; Examples in Common Lisp(search "e" "Hello mate") ; returns 1(search "z" "word") ; returns NIL // Examples in C#"Hello mate".IndexOf("e"); // returns 1"Hello mate".IndexOf("e", 4); // returns 9"word".IndexOf("z"); // returns -1 ; Examples in Scheme(use-modules (srfi srfi-13))(string-contains "Hello mate" "e") ; returns 1(string-contains "word" "z") ; returns #f ' Examples in Visual BasicInStr("Hello mate", "e") ' returns 2InStr(5, "Hello mate", "e") ' returns 10InStr("word", "z") ' returns 0 " Examples in Smalltalk "'Hello mate' indexOfSubCollection:'ate' "returns 8"'Hello mate' indexOfSubCollection:'late' "returns 0"I'Hello mate' indexOfSubCollection:'late' ifAbsent:[ 99 ] "returns 99"'Hello mate' indexOfSubCollection:'late' ifAbsent:[ self error ] "raises an exception"
Find characterDefinition | find character(string,char) returns integer | Description | Returns the position of the start of the first occurrence of the character char in string. If the character is not found most of these routines return an invalid index value – -1 where indexes are 0-based, 0 where they are 1-based – or some value to be interpreted as Boolean FALSE. This can be accomplished as a special case of #Find, with a string of one character; but it may be simpler or more efficient in many languages to locate just one character. Also, in many languages, characters and strings are different types, so it is convenient to have such a function. | Related | find |
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char in string(char, pos, string[startpos:]) | ALGOL 68 | returns BOOL: TRUE or FALSE, and position in REF INT pos. | instr(string, any char«,startpos») (char, can contain more them one char, in which case the position of the first appearance of any of them is returned.) | FreeBASIC | returns 0 | strchr(string,char) | C, C++ (char * only, returns pointer to character) | returns NULL | std.string.find(string, dchar) | D | returns -1 | string.find(char«,startpos») | C++ (std::string only) | returns std::string::npos | pos(string, char«, startpos») | Seed7 | returns 0 | strings.IndexRune(string,char) | Go | returns -1 | string.indexOf(char«,startpos») | Java, JavaScript | returns -1 | string.IndexOf(char«,startpos«, charcount»») | VB .NET, C#, Windows PowerShell, F# | returns -1 | (position char string) | Common Lisp | returns NIL | (char-index char string) | ISLISP | returns nil | List.elemIndex char string | Haskell (returns Just index) | returns Nothing | String.index string char | OCaml | raises Not_found | position = SCAN (string, set «, back» «, kind») or position = VERIFY (string, set «, back» «, kind»)[a] | Fortran | returns zero | string indexOf: char ifAbsent: aBlock string indexOf: char string includes: char | Smalltalk | evaluate aBlock which is a BlockClosure (or any object understanding value) returns 0 returns true or false | index(string, char, startpos ) | PL/I1 | returns 0 (positions start at 1) |
1startpos is IBM extension. // Examples in C#"Hello mate".IndexOf('e'); // returns 1"word".IndexOf('z') // returns -1 ; Examples in Common Lisp(position #\e "Hello mate") ; returns 1(position #\z "word") ; returns NIL ^a Given a set of characters, SCAN returns the position of the first character found,[1] while VERIFY returns the position of the first character that does not belong to the set.[2] FormatDefinition | format(formatstring, items) returns string | Description | Returns the formatted string representation of one or more items. |
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associate(file, string); putf(file, $formatstring$, items) | ALGOL 68 | ALGOL | Format(item, formatstring) | VB | | sprintf(formatstring, items) | Perl, PHP, Ruby | C | io_lib:format(formatstring, items) | Erlang | | sprintf(outputstring, formatstring, items) | C, C++ (char * only) | C | std.string.format(formatstring, items) | D | C | Format(formatstring, items) | Object Pascal (Delphi) | | fmt.Sprintf(formatstring, items) | Go | C | printf -v outputstring formatstring items | Bash shell | C | formatstring % (items) | Python, Ruby | C | formatstring.format(items) | Python 3.x | .NET | Printf.sprintf formatstring items | OCaml, F# (formatstring must be a fixed literal at compile time for it to have the correct type) | C | Text.Printf.printf formatstring items | Haskell (GHC) | C | String.format(formatstring, items) | Java | C | String.Format(formatstring, items) | VB .NET, C#, F# | .NET | (format formatstring items) | Scheme (SRFI 28) | Lisp | (format nil formatstring items) | Common Lisp | Lisp | (format formatstring items) | Clojure | Lisp | formatstring -f items | Windows PowerShell | .NET | [NSString stringWithFormat:formatstring, items] | Objective-C (NSString * only) | C | string.format(formatstring, items) (formatstring):format(items) | Lua | C | WRITE (outputstring, formatstring) items | Fortran | Fortran | put string(string) edit(items)(format) | PL/I | PL/I (similar to Fortran) |
// Example in C#String.Format("My {0} costs {1:C2}", "pen", 19.99); // returns "My pen costs $19.99" // Example in Object Pascal (Delphi)Format('My %s costs $%2f', ['pen', 19.99]); // returns "My pen costs $19.99" // Example in JavaString.format("My %s costs $%2f", "pen", 19.99); // returns "My pen costs $19.99" # Example in Python"My %s costs $%.2f" % ("pen", 19.99); # returns "My pen costs $19.99""My {0} costs ${1:.2f}".format("pen", 19.99); # returns "My pen costs $19.99" ; Example in Scheme(format "My ~a costs $~1,2F" "pen" 19.99) ; returns "My pen costs $19.99" /* example in PL/I */put string(some_string) edit('My ', 'pen', ' costs', 19.99)(a,a,a,p'$$$V.99')/* returns "My pen costs $19.99" */ InequalityTests if two strings are not equal. See also #Equality. |
string1 ne string2, or string1 NE string2 | ALGOL 68 - note: the operator "ne" is literally in bold type-font. | string1 /= string2 | ALGOL 68, Ada, Erlang, Fortran, Haskell | string1 <> string2 | BASIC, VB, VB .NET, Pascal, Object Pascal (Delphi), OCaml, PHP, Seed7, Standard ML, F# | string1 # string2 | BASIC (some implementations) | string1 ne string2 | Perl | (string<> string1 string2) | Scheme (SRFI 13) | (string/= string1 string2) | Common Lisp | (string/= string1 string2) | ISLISP | (not= string1 string2) | Clojure | string1 != string2 | C++ (std::string only), C#, Go, JavaScript (not similar), PHP (not similar), Python, Ruby, D, Mathematica | string1 !== string2 | JavaScript, PHP | string1 \= string2 | REXX | string1 ¬= string2 | PL/I | test string1 != string2, or [ string1 != string2 ] | Bourne Shell | string1 -ne string2, or -not [string]::Equals(string1, string2) | Windows PowerShell | string1 ~= string2 | Lua, Smalltalk |
// Example in C#"hello" != "world" // returns true ' Example in Visual Basic"hello" <> "world" ' returns true ; Example in Clojure(not= "hello" "world") ; ⇒ true # Example in Windows PowerShell"hello" -ne "world" # returns true indexsee #Find indexofsee #Find instrsee #Find instrrevsee #rfind joinDefinition | join(separator, list_of_strings) joins a list of strings with a separator | Description | Joins the list of strings into a new string, with the separator string between each of the substrings. Opposite of split. | Related | sprintf |
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std.string.join(array_of_strings, separator) | D | string:join(list_of_strings, separator) | Erlang | join(separator, list_of_strings) | Perl, PHP | implode(separator, array_of_strings) | PHP | separator.join(sequence_of_strings) | Python | array_of_strings.join(separator) | Ruby, JavaScript | (string-join array_of_strings separator) | Scheme (SRFI 13) | (format nil "~{~a~^separator~}" array_of_strings) | Common Lisp | (clojure.string/join separator list_of_strings) (apply str (interpose separator list_of_strings)) | Clojure | strings.Join(array_of_strings, separator) | Go | join(array_of_strings, separator) | Seed7 | String.concat separator list_of_strings | OCaml | String.concatWith separator list_of_strings | Standard ML | Data.List.intercalate separator list_of_strings | Haskell (GHC 6.8+) | Join(array_of_strings, separator) | VB | String.Join(separator, array_of_strings) | VB .NET, C#, F# | &{$OFS=$separator; "$array_of_strings"}, or array_of_strings -join separator | Windows PowerShell | [array_of_strings componentsJoinedByString:separator] | Objective-C (NSString * only) | table.concat(table_of_strings, separator) | Lua | String streamContents: [ :stream | collectionOfAnything asStringOn: stream delimiter: separator ] | Smalltalk (Squeak, Pharo) |
// Example in C#String.Join("-", {"a", "b", "c"}) // "a-b-c" # Example in Perljoin( '-', ('a', 'b', 'c')); # 'a-b-c' # Example in Python"-".join(["a", "b", "c"]) # 'a-b-c' # Example in Ruby["a", "b", "c"].join("-") # 'a-b-c' ; Example in Scheme(use-modules (srfi srfi-13))(string-join '("a" "b" "c") "-") ; "a-b-c" lastindexofsee #rfind leftDefinition | left(string,n) returns string | Description | Returns the left n part of a string. If n is greater than the length of the string then most implementations return the whole string (exceptions exist - see code examples). |
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string (string'First .. string'First + n - 1) | Ada | string:substr(string, start, length) | Erlang | Left(string,n) | VB | LEFT$(string,n) | BASIC | left(string,n) | FreeBASIC, Ingres | left(string,n «,padchar») | REXX, Erlang | substr(string, 0, n) | AWK (changes string), Perl, PHP | string[:n] | Python | string[0, n] string[0..n - 1] | Ruby | string.substr(0,n) | C++ (std::string only) | string[0 .. n] | D (if n is larger than the length of the string, then in Debug mode ArrayRangeException is thrown, in Release mode, the behaviour is unspecified) | string[ .. n] | Seed7 | string.Substring(0,n) | VB .NET, C#, Windows PowerShell, F# | leftstr(string, n) | Pascal, Object Pascal (Delphi) | string.substring(0,n) | Java, JavaScript (if n is larger than the length of the string, Java will throw an IndexOutOfBoundsException) | (string-take string n) | Scheme (SRFI 13) | take n string | Haskell | (apply str (take n string)) | Clojure | [string substringToIndex:n] | Objective-C (NSString * only) | String.extract (string, n, NONE) | Standard ML | String.sub string 0 n | OCaml (if n is larger than length of string, raises Invalid_argument) | string.[..n] | F# | string.sub(string, 1, n) (string):sub(1, n) | Lua | string first: n | Smalltalk (Squeak, Pharo) | string(:n) | Fortran | StringTake[string, n] | Mathematica (if n is larger than length of string, throw the message "StringTake::take:") |
/* Examples in REXX */left("abcde", 3) /* returns "abc" */left("abcde", 8) /* returns "abcde " */left("abcde", 8, "*") /* returns "abcde***" */ ; Examples in Scheme(use-modules (srfi srfi-13))(string-take "abcde", 3) ; returns "abc" (string-take "abcde", 8) ; error ' Examples in Visual BasicLeft("sandroguidi", 3) ' returns "san" Left("sandroguidi", 100) ' returns "sandroguidi" lensee #length
lengthDefinition | length(string) returns an integer number | Description | Returns the length of a string (not counting the null terminator or any other of the string's internal structural information). An empty string returns a length of 0. |
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string'Length | | Ada | UPB string | | ALGOL 68 | length(string) | | Ingres, Perl, Pascal, Object Pascal (Delphi), REXX, Seed7, SQL, PL/I | len(string) | | BASIC, FreeBASIC, Python, Go | length(string), string:len(string) | | Erlang | Len(string) | | VB | string.Length | Number of 16-bit UTF-16-encoded blocks | VB .NET, C#, Windows PowerShell, F# | string.size OR string.length | Number of bytes (Ruby lacks Unicode support) | Ruby | strlen(string) | Number of bytes | C, C++ (char * only), PHP | string.length() | | C++ (std::string only) | string.length | | D | string.length() | Number of 16-bit UTF-16-encoded blocks | Java | string.length | | JavaScript | (string-length string) | | Scheme | (length string) | | Common Lisp | (length string) | | ISLISP | (count string) | | Clojure | String.length string | | OCaml | size string | | Standard ML | length string | Number of Unicode codepoints | Haskell | [string length] | | Objective-C (NSString * only) | string.len(string) (string):len() #string | | Lua | string size | | Smalltalk | LEN(string), or LEN_TRIM(string) | | Fortran | StringLength[string] | | Mathematica |
// Examples in C#"hello".Length; // returns 5"".Length; // returns 0 # Examples in Erlangstring:len("hello"). % returns 5string:len(""). % returns 0 # Examples in Perllength("hello"); # returns 5length(""); # returns 0 ' Examples in Visual BasicLen("hello") ' returns 5Len("") ' returns 0 //Examples in Objective-C[@"hello" Length] //returns 5[@"" Length] //returns 0 -- Examples in Lua("hello"):len() -- returns 5#"" -- returns 0 locatesee #Find
LowercaseDefinition | lowercase(string) returns string | Description | Returns the string in lower case. |
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LCase(string) | VB | lcase(string) | FreeBASIC | lc(string) | Perl | tolower(char) | C (operates on one character) | std.string.toLower(string) | D | transform(string.begin(), string.end(), result.begin(), ::tolower)[3] | C++ (std::string only, result is stored in string result which is at least as long as string, and may or may not be string itself) | lowercase(string) | Object Pascal (Delphi) | strtolower(string) | PHP | echo "string" | tr 'A-Z' 'a-z' | Unix | string.lower() | Python | string.downcase | Ruby (only ASCII characters as Ruby lacks Unicode support) | strings.ToLower(string) | Go | (string-downcase string) | Scheme (R6RS), Common Lisp | (lower-case string) | Clojure | String.lowercase string | OCaml | String.map Char.toLower string | Standard ML | map Char.toLower string | Haskell | string.toLowerCase() | Java, JavaScript | to_lower(string) | Erlang | string.ToLower() | VB .NET, C#, Windows PowerShell, F# | [string lowercaseString] | Objective-C (NSString * only) | string.lower(string) (string):lower() | Lua | string asLowercase | Smalltalk | LOWER(string) | SQL | lowercase(string) | PL/I1 | ToLowerCase[string] | Mathematica |
1IBM extension. // Example in C#"Wiki means fast?".ToLower(); // "wiki means fast?" ; Example in Scheme(use-modules (srfi srfi-13))(string-downcase "Wiki means fast?") ; "wiki means fast?" /* Example in C */#include <ctype.h>#include <stdio.h>int main(void) { char string[] = "Wiki means fast?"; int i; for (i = 0; i < sizeof(string) - 1; ++i) { /* transform characters in place, one by one */ string[i] = tolower(string[i]); } puts(string); /* "wiki means fast?" */ return 0;} midsee #substring1
partitionDefinition | <string>.partition(separator) returns the sub-string before the separator; the separator; then the sub-string after the separator. | Description | Splits the given string by the separator and returns the three substrings that together make the original. |
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string.partition(separator) | Python, Ruby(1.9+) | lists:partition(pred, string) | Erlang | split /(separator)/, string, 2 | Perl |
# Examples in Python"Spam eggs spam spam and ham".partition('spam') # ('Spam eggs ', 'spam', ' spam and ham')"Spam eggs spam spam and ham".partition('X') # ('Spam eggs spam spam and ham', "", "") # Examples in Perlsplit /(spam)/'Spam eggs spam spam and ham',2; # ('Spam eggs ', 'spam', ' spam and ham');split /(X)/'Spam eggs spam spam and ham',2; # ('Spam eggs spam spam and ham');
replaceDefinition | replace(string, find, replace) returns string | Description | Returns a string with find occurrences changed to replace. |
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changestr(find, string, replace) | REXX | std.string.replace(string, find, replace) | D | Replace(string, find, replace) | VB | string.Replace(find, replace) | VB .NET, C#, F# | str_replace(find, replace, string) | PHP | re:replace(string, find, replace, «{return, list}») | Erlang | string.replace(find, replace) | Python, Java (1.5+) | string.replaceAll(find_regex, replace)[4] | Java | string.gsub(find, replace) | Ruby | string =~ s/find_regex/replace/g[4] | Perl | string.replace(find, replace, "g") (third parameter is non-standard) or string.replace(/find_regex/g, replace)[4] | JavaScript | echo "string" | sed 's/find_regex/replace/g'[4] | Unix | string.replace(find, replace), or string -replace find_regex, replace[4] | Windows PowerShell | Str.global_replace (Str.regexp_string find) replace string | OCaml | [string stringByReplacingOccurrencesOfString:find withString:replace] | Objective-C (NSString * only) | string.gsub(string, find, replace) (string):gsub(find, replace) | Lua | string copyReplaceAll: find with: replace | Smalltalk (Squeak, Pharo) | string map {find replace} string | Tcl | StringReplace[string, find -> replace] | Mathematica |
// Examples in C#"effffff".Replace("f", "jump"); // returns "ejumpjumpjumpjumpjumpjump""blah".Replace("z", "y"); // returns "blah" // Examples in Java"effffff".replace("f", "jump"); // returns "ejumpjumpjumpjumpjumpjump""effffff".replaceAll("f*", "jump"); // returns "ejump" ' Examples in Visual BasicReplace("effffff", "f", "jump") ' returns "ejumpjumpjumpjumpjumpjump"Replace("blah", "z", "y") ' returns "blah" # Examples in Windows PowerShell"effffff" -replace "f", "jump" # returns "ejumpjumpjumpjumpjumpjump""effffff" -replace "f*", "jump" # returns "ejump" reverseDefinition | reverse(string) | Description | Reverses the order of the characters in the string. |
# Example in Perlreverse "hello" # returns "olleh" # Example in Python"hello"[::-1] # returns "olleh" ; Example in Scheme(use-modules (srfi srfi-13))(string-reverse "hello") ; returns "olleh" rfindDefinition | rfind(string,substring) returns integer | Description | Returns the position of the start of the last occurrence of substring in string. If the substring is not found most of these routines return an invalid index value – -1 where indexes are 0-based, 0 where they are 1-based – or some value to be interpreted as Boolean FALSE. | Related | instr |
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InStrRev(«startpos,» string,substring) | VB | returns 0 | instrrev(«startpos,» string,substring) | FreeBASIC | returns 0 | rindex(string,substring«,startpos») | Perl | returns -1 | strrpos(string,substring«,startpos») | PHP | returns FALSE | string.rfind(substring«,startpos») | C++ (std::string only) | returns std::string::npos | std.string.rfind(string, substring) | D | returns -1 | string.rfind(substring«,startpos«, endpos»») | Python | returns -1 | rpos(string, substring«,startpos») | Seed7 | returns 0 | string.rindex(substring«,startpos») | Ruby | returns nil | strings.LastIndex(string, substring) | Go | returns -1 | string.lastIndexOf(substring«,startpos») | Java, JavaScript | returns -1 | string.LastIndexOf(substring«,startpos«, charcount»») | VB .NET, C#, Windows PowerShell, F# | returns -1 | (search substring string :from-end t) | Common Lisp | returns NIL | [string rangeOfString:substring options:NSBackwardsSearch].location | Objective-C (NSString * only) | returns NSNotFound | Str.search_backward (Str.regexp_string substring) string (Str.length string - 1) | OCaml | raises Not_found | string.match(string, '.*()'..substring) string:match('.*()'..substring) | Lua | returns nil | Ada.Strings.Unbounded.Index(Source => string, Pattern => substring, Going => Ada.Strings.Backward) | Ada | returns 0 |
; Examples in Common Lisp(search "e" "Hello mate" :from-end t) ; returns 9(search "z" "word" :from-end t) ; returns NIL // Examples in C#"Hello mate".LastIndexOf("e"); // returns 9"Hello mate".LastIndexOf("e", 4); // returns 1"word".LastIndexOf("z"); // returns -1 ' Examples in Visual BasicInStrRev("Hello mate", "e") ' returns 10InStrRev(5, "Hello mate", "e") ' returns 2InStrRev("word", "z") ' returns 0
rightDefinition | right(string,n) returns string | Description | Returns the right n part of a string. If n is greater than the length of the string then most implementations return the whole string (exceptions exist - see code examples). |
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string (string'Last - n + 1 .. string'Last) | Ada | Right(string,n) | VB | RIGHT$(string,n) | BASIC | right(string,n) | FreeBASIC, Ingres | string.substring(string.length()-n) | Java | string.slice(-n) | JavaScript[5] | right(string,n «,padchar») | REXX, Erlang | substr(string,-n) | Perl, PHP | string[-n:] | Python | (string-take-right string n) | Scheme (SRFI 13) | string[-n..-1] | Ruby | string[$-n .. $] | D (if n is larger than length of string, then in Debug mode ArrayRangeException is thrown, and unspecified behaviour in Release mode) | String.sub string (String.length string - n) n | OCaml (if n is larger than length of string, raises Invalid_argument) | string.sub(string, -n) (string):sub(-n) | Lua | string last: n | Smalltalk (Squeak, Pharo) | StringTake[string, -n] | Mathematica (if n is larger than length of string, throw the message "StringTake::take:") |
/* Examples in REXX */right("abcde", 3) /* returns "cde" */right("abcde", 8) /* returns " abcde" */right("abcde", 8, "*") /* returns "***abcde" */ ; Examples in Scheme(use-modules (srfi srfi-13))(string-take-right "abcde", 3) ; returns "cde" (string-take-right "abcde", 8) ; error ' Examples in Visual BasicRight("sandroguidi", 3) ' returns "idi" Right("sandroguidi", 100) ' returns "sandroguidi" // Examples in Java; extract rightmost 4 charactersString str = "CarDoor";str.substring(str.length()-4); // returns 'Door'
rpartitionDefinition | <string>.rpartition(separator) Searches for the separator from right-to-left within the string then returns the sub-string before the separator; the separator; then the sub-string after the separator. | Description | Splits the given string by the right-most separator and returns the three substrings that together make the original. |
# Examples in Python"Spam eggs spam spam and ham".rpartition('spam') ### ('Spam eggs spam ', 'spam', ' and ham')"Spam eggs spam spam and ham".rpartition('X') ### ("", "", 'Spam eggs spam spam and ham') slicesee #substring
splitDefinition | <string>.split(separator[, limit]) splits a string on separator, optionally only up to a limited number of substrings | Description | Splits the given string by occurrences of the separator (itself a string) and returns a list (or array) of the substrings. If limit is given, after limit - 1 separators have been read, the rest of the string is made into the last substring, regardless of whether it has any separators in it. The Scheme and Erlang implementations are similar but differ in several ways. JavaScript differs also in that it cuts, it does not put the rest of the string into the last element. See the example here. Opposite of join. |
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split(/separator/, string«, limit») | Perl | explode(separator, string«, limit») | PHP | string.split(separator«, limit-1») | Python | string.split(separator«, limit») | Javascript, Java, Ruby | string:tokens(string, sepchars) | Erlang | strings.Split(string, separator) strings.SplitN(string, separator, limit) | Go | (string-tokenize string« charset« start« end»»») | Scheme (SRFI 13) | Split(string, sepchars«, limit») | VB | string.Split(sepchars«, limit«, options»») | VB .NET, C#, F# | string -split separator«, limit«, options»» | Windows PowerShell | Str.split (Str.regexp_string separator) string | OCaml | std.string.split(string, separator) | D | [string componentsSeparatedByString:separator] | Objective-C (NSString * only) | TStringList.Delimiter, TStringList.DelimitedText | Object Pascal | StringSplit[string, separator«, limit»] | Mathematica |
// Example in C#"abc,defgh,ijk".Split(','); // {"abc", "defgh", "ijk"}"abc,defgh;ijk".Split(',', ';'); // {"abc", "defgh", "ijk"} % Example in Erlangstring:tokens("abc;defgh;ijk", ";"). % ["abc", "defgh", "ijk"] // Examples in Java"abc,defgh,ijk".split(","); // {"abc", "defgh", "ijk"}"abc,defgh;ijk".split(",|;"); // {"abc", "defgh", "ijk"} # Example in Pascalvar lStrings: TStringList; lStr: string;begin lStrings := TStringList.Create; lStrings.Delimiter := ','; lStrings.DelimitedText := 'abc,defgh,ijk'; lStr := lStrings.Strings[0]; // 'abc' lStr := lStrings.Strings[1]; // 'defgh' lStr := lStrings.Strings[2]; // 'ijk'end; # Examples in Perlsplit(/spam/, 'Spam eggs spam spam and ham'); # ('Spam eggs ', ' ', ' and ham')split(/X/, 'Spam eggs spam spam and ham'); # ('Spam eggs spam spam and ham') sprintfsee #Format stripsee #trim
strcmpsee #Compare (integer result)
substring1Definition | substring(string, startpos, endpos) returns string substr(string, startpos, numChars) returns string | Description | Returns a substring of string between starting at startpos and endpos, or starting at startpos of length numChars. The resulting string is truncated if there are fewer than numChars characters beyond the starting point. endpos represents the index after the last character in the substring. |
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string[startpos:endpos] | ALGOL 68 (changes base index) | string (startpos .. endpos) | Ada (changes base index) | Mid(string, startpos, numChars) | VB | mid(string, startpos, numChars) | FreeBASIC | MID$(string, startpos, numChars) | BASIC | substr(string, startpos, numChars) | AWK (changes string), Perl2,4, PHP2,4 | substr(string, startpos «,numChars, padChar») | REXX | string[startpos:endpos] | Python2,3, Go | string[startpos, numChars] string[startpos .. endpos-1] string[startpos ... endpos] | Ruby2,3 | string[startpos .. endpos] string[startpos len numChars] | Seed7 | string.slice(startpos«, endpos») | JavaScript2,3 | string.substr(startpos«, numChars») | C++ (std::string only), JavaScript | string.Substring(startpos, numChars) | VB .NET, C#, Windows PowerShell, F# | string.substring(startpos«, endpos») | Java, JavaScript | copy(string, startpos, numChars) | Object Pascal (Delphi) | (substring string startpos endpos) | Scheme | (subseq string startpos endpos) | Common Lisp | (subseq string startpos endpos) | ISLISP | String.sub string startpos numChars | OCaml | substring (string, startpos, numChars) | Standard ML | string:sub_string(string, startpos, endpos) string:substr(string, startpos, numChars) | Erlang | char result[numChars+1] = ""; strncat(result, string + startpos, numChars); | C | string[startpos .. endpos+1) | D | take numChars $ drop startpos string | Haskell | [string substringWithRange:NSMakeRange(startpos, numChars)] | Objective-C (NSString * only) | string.[startpos..endpos] | F# | string.sub(string, startpos, endpos) (string):sub(startpos, endpos) | Lua2,3 | string copyFrom: startpos to: endpos | Smalltalk | string(startpos:endpos) | Fortran | SUBSTRING(string FROM startpos «FOR numChars») | SQL | StringTake[string, {startpos, endpos}] | Mathematica2,3 |
- See CharAt for base of startpos/endpos.
- In this language, startpos can be negative, which indicates to start that number of places before the end of the string.
- In this language, endpos can be negative, which indicates to end that number of places before the end of the string.
- In this language, numChars can be negative, which indicates to end that number of places before the end of the string.
// Examples in C#"abc".Substring(1, 1): // returns "b""abc".Substring(1, 2); // returns "bc""abc".Substring(1, 6); // error ; Examples in Common Lisp(subseq "abc" 1 2) ; returns "b"(subseq "abc" 2) ; returns "bc" <source lang="text">% Examples in Erlangstring:substr("abc", 2, 1). % returns "b"string:substr("abc", 2). % returns "bc" # Examples in Python"abc"[1:2] # returns "b""abc"[1:3] # returns "bc" /* Examples in REXX */substr("abc", 2, 1) /* returns "b" */substr("abc", 2) /* returns "bc" */substr("abc", 2, 6) /* returns "bc " */substr("abc", 2, 6, "*") /* returns "bc****" */
UppercaseDefinition | uppercase(string) returns string | Description | Returns the string in upper case. |
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UCase(string) | VB | ucase(string) | FreeBASIC | toupper(string) | AWK (changes string) | uc(string) | Perl | toupper(char) | C (operates on one character) | std.string.toUpper(string) | D | transform(string.begin(), string.end(), result.begin(), toupper)[3] | C++ (std::string only, result is stored in string result which is at least as long as string, and may or may not be string itself) | uppercase(string) | Object Pascal (Delphi) | upcase(char) | Object Pascal (Delphi) (operates on one character) | strtoupper(string) | PHP | echo "string" | tr 'a-z' 'A-Z' | Unix | translate(string), or
UPPER variables, or PARSE UPPER VAR SrcVar DstVar | REXX | string.upper() | Python | string.upcase | Ruby (only ASCII characters as Ruby lacks Unicode support) | strings.ToUpper(string) | Go | (string-upcase string) | Scheme, Common Lisp | String.uppercase string | OCaml | String.map Char.toUpper string | Standard ML | map Char.toUpper string | Haskell | string.toUpperCase() | Java, JavaScript | to_upper(string) | Erlang | string.ToUpper() | VB .NET, C#, Windows PowerShell, F# | [string uppercaseString] | Objective-C (NSString * only) | string.upper(string) (string):upper() | Lua | string asUppercase | Smalltalk | UPPER(string) | SQL | ToUpperCase[string] | Mathematica |
// Example in C#"Wiki means fast?".ToUpper(); // "WIKI MEANS FAST?" /* Example in REXX */translate("Wiki means fast?") /* "WIKI MEANS FAST?" */ /* Example #2 */A='This is an example.'UPPER A /* "THIS IS AN EXAMPLE." */ /* Example #3 */A='upper using Translate Function.'Translate UPPER VAR A Z /* Z="UPPER USING TRANSLATE FUNCTION." */ ; Example in Scheme(use-modules (srfi srfi-13))(string-upcase "Wiki means fast?") ; "WIKI MEANS FAST?" ' Example in Visual BasicUCase("Wiki means fast?") ' "WIKI MEANS FAST?" trimtrim or strip is used to remove whitespace from the beginning, end, or both beginning and end, of a string. Notes- ^ http://fortranwiki.org/fortran/show/s can
- ^ http://fortranwiki.org/fortran/show/v erify
- ^ a b The
transform function exists in the std:: namespace. You must include the <algorithm> header file to use it. The tolower and toupper functions are in the global namespace, obtained by the <ctype.h> header file. The std::tolower and std::toupper names are overloaded and cannot be passed to std::transform without a cast to resolve a function overloading ambiguity, e.g. std::transform(string.begin(), string.end(), result.begin(), (int (*)(int))std::tolower); - ^ a b c d e The "find" string in this construct is interpreted as a regular expression. Certain characters have special meaning in regular expressions. If you want to find a string literally, you need to quote the special characters.
- ^ http://es5.github.com/#x15.5.4.13
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