Package Modelica.​Utilities.​Strings
Operations on strings

Information

Library content

Package Strings contains functions to manipulate strings.

In the table below an example call to every function is given using the default options.

FunctionDescription
len = length(string) Returns length of string
string2 = substring(string1,startIndex,endIndex) Returns a substring defined by start and end index
result = repeat(n)
result = repeat(n,string)
Repeat a blank or a string n times.
result = compare(string1, string2) Compares two substrings with regards to alphabetical order
identical = isEqual(string1,string2) Determine whether two strings are identical
result = count(string,searchString) Count the number of occurrences of a string
index = find(string,searchString) Find first occurrence of a string in another string
index = findLast(string,searchString) Find last occurrence of a string in another string
string2 = replace(string,searchString,replaceString) Replace one or all occurrences of a string
stringVector2 = sort(stringVector1) Sort vector of strings in alphabetic order
hash = hashString(string) Create a hash value of a string
(token, index) = scanToken(string,startIndex) Scan for a token (Real/Integer/Boolean/String/Identifier/Delimiter/NoToken)
(number, index) = scanReal(string,startIndex) Scan for a Real constant
(number, index) = scanInteger(string,startIndex) Scan for an Integer constant
(boolean, index) = scanBoolean(string,startIndex) Scan for a Boolean constant
(string2, index) = scanString(string,startIndex) Scan for a String constant
(identifier, index) = scanIdentifier(string,startIndex) Scan for an identifier
(delimiter, index) = scanDelimiter(string,startIndex) Scan for delimiters
scanNoToken(string,startIndex) Check that remaining part of string consists solely of
white space or line comments ("// ...\n").
syntaxError(string,index,message) Print a "syntax error message" as well as a string and the
index at which scanning detected an error

The functions "compare", "isEqual", "count", "find", "findLast", "replace", "sort" have the optional input argument caseSensitive with default true. If false, the operation is carried out without taking into account whether a character is upper or lower case.

Extends from Modelica.​Icons.​FunctionsPackage (Icon for packages containing functions).

Package Contents

NameDescription
AdvancedAdvanced scanning functions
compareCompare two strings lexicographically
countCount the number of non-overlapping occurrences of a string
findFind first occurrence of a string within another string
findLastFind last occurrence of a string within another string
hashStringCreate a hash value of a string
isEmptyReturn true if a string is empty (has only white space characters)
isEqualDetermine whether two strings are identical
lengthReturn length of string
repeatRepeat a string n times
replaceReplace non-overlapping occurrences of a string from left to right
scanBooleanScan for the next Boolean number and trigger an assert if not present
scanDelimiterScan for the next delimiter and trigger an assert if not present
scanIdentifierScan for the next Identifier and trigger an assert if not present
scanIntegerScan for the next Integer number and trigger an assert if not present
scanNoTokenScan string and check that it contains no more token
scanRealScan for the next Real number and trigger an assert if not present
scanStringScan for the next Modelica string and trigger an assert if not present
scanTokenScan for the next token and return it
sortSort vector of strings in alphabetic order
substringReturn a substring defined by start and end index
syntaxErrorPrint an error message, a string and the index at which scanning detected an error

Function Modelica.​Utilities.​Strings.​length
Return length of string

Information

Syntax

Strings.length(string);

Description

Returns the number of characters of "string".

Extends from Modelica.​Icons.​Function (Icon for functions).

Inputs

TypeNameDescription
Stringstring 

Outputs

TypeNameDescription
IntegerresultNumber of characters of string

Function Modelica.​Utilities.​Strings.​substring
Return a substring defined by start and end index

Information

Syntax

string2 = Strings.substring(string, startIndex, endIndex);

Description

This function returns the substring from position startIndex up to and including position endIndex of "string" .

If index, startIndex, or endIndex are not correct, e.g., if endIndex > length(string), an assert is triggered.

Example

  string1 := "This is line 111";
  string2 := Strings.substring(string1,9,12); // string2 = "line"

Extends from Modelica.​Icons.​Function (Icon for functions).

Inputs

TypeNameDescription
StringstringString from which a substring is inquired
IntegerstartIndexCharacter position of substring begin (index=1 is first character in string)
IntegerendIndexCharacter position of substring end

Outputs

TypeNameDescription
StringresultString containing substring string[startIndex:endIndex]

Function Modelica.​Utilities.​Strings.​repeat
Repeat a string n times

Information

Syntax

string2 = Strings.repeat(n);
string2 = Strings.repeat(n, string=" ");

Description

The first form returns a string consisting of n blanks.

The second form returns a string consisting of n substrings defined by the optional argument "string".

Extends from Modelica.​Icons.​Function (Icon for functions).

Inputs

TypeNameDescription
IntegernNumber of occurrences
StringstringString that is repeated

Outputs

TypeNameDescription
StringrepeatedStringString containing n concatenated strings

Function Modelica.​Utilities.​Strings.​compare
Compare two strings lexicographically

Information

Syntax

result = Strings.compare(string1, string2);
result = Strings.compare(string1, string2, caseSensitive=true);

Description

Compares two strings. If the optional argument caseSensitive=false, upper case letters are treated as if they would be lower case letters. The result of the comparison is returned as:

  result = Modelica.Utilities.Types.Compare.Less     // string1 < string2
         = Modelica.Utilities.Types.Compare.Equal    // string1 = string2
         = Modelica.Utilities.Types.Compare.Greater  // string1 > string2

Comparison is with regards to lexicographical order, e.g., "a" < "b";

Extends from Modelica.​Icons.​Function (Icon for functions).

Inputs

TypeNameDescription
Stringstring1 
Stringstring2 
BooleancaseSensitive= false, if case of letters is ignored

Outputs

TypeNameDescription
CompareresultResult of comparison

Function Modelica.​Utilities.​Strings.​isEqual
Determine whether two strings are identical

Information

Syntax

Strings.isEqual(string1, string2);
Strings.isEqual(string1, string2, caseSensitive=true);

Description

Compare whether two strings are identical, optionally ignoring case.

Extends from Modelica.​Icons.​Function (Icon for functions).

Inputs

TypeNameDescription
Stringstring1 
Stringstring2 
BooleancaseSensitive= false, if lower and upper case are ignored for the comparison

Outputs

TypeNameDescription
BooleanidenticalTrue, if string1 is identical to string2

Function Modelica.​Utilities.​Strings.​isEmpty
Return true if a string is empty (has only white space characters)

Information

Syntax

Strings.isEmpty(string);

Description

Returns true if the string has no characters or if the string consists only of white space characters. Otherwise, false is returned.

Example

  isEmpty("");       // returns true
  isEmpty("   ");    // returns true
  isEmpty("  abc");  // returns false
  isEmpty("a");      // returns false

Extends from Modelica.​Icons.​Function (Icon for functions).

Inputs

TypeNameDescription
Stringstring 

Outputs

TypeNameDescription
BooleanresultTrue, if string is empty

Function Modelica.​Utilities.​Strings.​count
Count the number of non-overlapping occurrences of a string

Information

Syntax

Strings.count(string, searchString)
Strings.count(string, searchString, startIndex=1,
                     caseSensitive=true)

Description

Returns the number of non-overlapping occurrences of string "searchString" in "string". The search is started at index "startIndex" (default = 1). If the optional argument "caseSensitive" is false, for the counting it does not matter whether a letter is upper or lower case.

Extends from Modelica.​Icons.​Function (Icon for functions).

Inputs

TypeNameDescription
StringstringString that is analyzed
StringsearchStringString that is searched for in string
IntegerstartIndexStart search at index startIndex
BooleancaseSensitive= false, if lower and upper case are ignored for count

Outputs

TypeNameDescription
IntegerresultNumber of occurrences of 'searchString' in 'string'

Function Modelica.​Utilities.​Strings.​find
Find first occurrence of a string within another string

Information

Syntax

index = Strings.find(string, searchString);
index = Strings.find(string, searchString, startIndex=1,
                     caseSensitive=true);

Description

Finds first occurrence of "searchString" within "string" and return the corresponding index. Start search at index "startIndex" (default = 1). If the optional argument "caseSensitive" is false, lower and upper case are ignored for the search. If "searchString" is not found, a value of "0" is returned.

Extends from Modelica.​Icons.​Function (Icon for functions).

Inputs

TypeNameDescription
StringstringString that is analyzed
StringsearchStringString that is searched for in string
IntegerstartIndexStart search at index startIndex
BooleancaseSensitive= false, if lower and upper case are ignored for the search

Outputs

TypeNameDescription
IntegerindexIndex of the beginning of the first occurrence of 'searchString' within 'string', or zero if not present

Function Modelica.​Utilities.​Strings.​findLast
Find last occurrence of a string within another string

Information

Syntax

index = Strings.findLast(string, searchString);
index = Strings.findLast(string, searchString,
                         startIndex=length(string), caseSensitive=true,

Description

Finds first occurrence of "searchString" within "string" when searching from the last character of "string" backwards, and return the corresponding index. Start search at index "startIndex" (default = 0; if startIndex = 0, search starts at length(string)). If the optional argument "caseSensitive" is false, lower and upper case are ignored for the search. If "searchString" is not found, a value of "0" is returned.

Extends from Modelica.​Icons.​Function (Icon for functions).

Inputs

TypeNameDescription
StringstringString that is analyzed
StringsearchStringString that is searched for in string
IntegerstartIndexStart search at index startIndex. If startIndex = 0, start at length(string)
BooleancaseSensitive= false, if lower and upper case are ignored for the search

Outputs

TypeNameDescription
IntegerindexIndex of the beginning of the last occurrence of 'searchString' within 'string', or zero if not present

Function Modelica.​Utilities.​Strings.​replace
Replace non-overlapping occurrences of a string from left to right

Information

Syntax

Strings.replace(string, searchString, replaceString);
Strings.replace(string, searchString, replaceString,
                startIndex=1, replaceAll=true, caseSensitive=true);

Description

Search in "string" for "searchString" and replace the found substring by "replaceString".

The function returns the "string" with the performed replacements.

Extends from Modelica.​Icons.​Function (Icon for functions).

Inputs

TypeNameDescription
StringstringString to be modified
StringsearchStringReplace non-overlapping occurrences of 'searchString' in 'string' with 'replaceString'
StringreplaceStringString that replaces 'searchString' in 'string'
IntegerstartIndexStart search at index startIndex
BooleanreplaceAllif false, replace only the first occurrence, otherwise all occurrences
BooleancaseSensitive= false, if lower and upper case are ignored when searching for searchString

Outputs

TypeNameDescription
StringresultResultant string of replacement operation

Function Modelica.​Utilities.​Strings.​sort
Sort vector of strings in alphabetic order

Information

Syntax

stringVector2 = Streams.sort(stringVector1);
stringVector2 = Streams.sort(stringVector1, caseSensitive=true);

Description

Function sort(..) sorts a string vector stringVector1 in lexicographical order and returns the result in stringVector2. If the optional argument "caseSensitive" is false, lower and upper case letters are not distinguished.

Example

  s1 = {"force", "angle", "pressure"};
  s2 = Strings.sort(s1);
       -> s2 = {"angle", "force", "pressure"};

Extends from Modelica.​Icons.​Function (Icon for functions).

Inputs

TypeNameDescription
StringstringVector1[:]vector of strings
BooleancaseSensitive= false, if lower and upper case are ignored when comparing elements of stringVector1

Outputs

TypeNameDescription
StringstringVector2[size(stringVector1, 1)]stringVector1 sorted in alphabetical order

Function Modelica.​Utilities.​Strings.​hashString
Create a hash value of a string

Information

Syntax

hash = Strings.hashString(string);

Description

Returns an Integer hash value of the provided string (the hash can be any Integer, including zero or a negative number).

Example

  hashString("this is a test")     // =  1827717433
  hashString("Controller.noise1")  // = -1025762750

Extends from Modelica.​Icons.​Function (Icon for functions).

Inputs

TypeNameDescription
StringstringThe string to create a hash from

Outputs

TypeNameDescription
IntegerhashThe hash value of string

Function Modelica.​Utilities.​Strings.​scanToken
Scan for the next token and return it

Information

Syntax

(token, nextIndex) = Strings.scanToken(string, startIndex, unsigned=false);

Description

Function scanToken scans the string starting at index "startIndex" and returns the next token, as well as the index directly after the token. The returned token is a record that holds the type of the token and the value of the token:

token.tokenType Type of the token, see below
token.real Real value if tokenType == TokenType.RealToken
token.integer Integer value if tokenType == TokenType.IntegerToken
token.boolean Boolean value if tokenType == TokenType.BooleanToken
token.string String value if tokenType == TokenType.StringToken/IdentifierToken/DelimiterToken

Variable token.tokenType is an enumeration (emulated as a package with constants) that can have the following values:

   import T = Modelica.Utilities.Types.TokenType;
T.RealToken Modelica Real literal (e.g., 1.23e-4)
T.IntegerToken Modelica Integer literal (e.g., 123)
T.BooleanToken Modelica Boolean literal (e.g., false)
T.StringToken Modelica String literal (e.g., "string 123")
T.IdentifierToken Modelica identifier (e.g., "force_a")
T.DelimiterToken any character without white space that does not appear
as first character in the tokens above (e.g., "&")
T.NoToken White space, line comments and no other token
until the end of the string

Modelica line comments ("// ... end-of-line/end-of-string") as well as white space is ignored. If "unsigned=true", a Real or Integer literal is not allowed to start with a "+" or "-" sign.

Example

  import Modelica.Utilities.Strings;
  import T = Modelica.Utilities.Types.TokenType;
  (token, index) := Strings.scanToken(string);
  if token.tokenType == T.RealToken then
     realValue := token.real;
  elseif token.tokenType == T.IntegerToken then
     integerValue := token.integer;
  elseif token.tokenType == T.BooleanToken then
     booleanValue := token.boolean;
  elseif token.tokenType == T.Identifier then
     name := token.string;
  else
     Strings.syntaxError(string,index,"Expected Real, Integer, Boolean or identifier token");
  end if;

Extends from Modelica.​Icons.​Function (Icon for functions).

Inputs

TypeNameDescription
StringstringString to be scanned
IntegerstartIndexStart scanning of string at character startIndex
Booleanunsigned= true, if Real and Integer tokens shall not start with a sign

Outputs

TypeNameDescription
TokenValuetokenScanned token
IntegernextIndexIndex of character after the found token; = 0, if NoToken

Function Modelica.​Utilities.​Strings.​scanReal
Scan for the next Real number and trigger an assert if not present

Information

Syntax

             number = Strings.scanReal(string);
(number, nextIndex) = Strings.scanReal(string, startIndex=1,
                                            unsigned=false, message="");

Description

The first form, "scanReal(string)", scans "string" for a Real number with leading white space and returns the value.

The second form, "scanReal(string,startIndex,unsigned)", scans the string starting at index "startIndex", checks whether the next token is a Real literal and returns its value as a Real number, as well as the index directly after the Real number. If the optional argument "unsigned" is true, the real number shall not have a leading "+" or "-" sign.

If the required Real number with leading white space is not present in "string", an assert is triggered.

Extends from Modelica.​Icons.​Function (Icon for functions).

Inputs

TypeNameDescription
StringstringString to be scanned
IntegerstartIndexStart scanning of string at character startIndex
Booleanunsigned= true, if Real token shall not start with a sign
StringmessageMessage used in error message if scan is not successful

Outputs

TypeNameDescription
RealnumberValue of real number
IntegernextIndexindex of character after the found number

Function Modelica.​Utilities.​Strings.​scanInteger
Scan for the next Integer number and trigger an assert if not present

Information

Syntax

             number = Strings.scanInteger(string);
(number, nextIndex) = Strings.scanInteger(string, startIndex=1,
                                               unsigned=false, message="");

Description

Function scanInteger scans the string starting at index "startIndex", checks whether the next token is an Integer literal and returns its value as an Integer number, as well as the index directly after the Integer number. An assert is triggered, if the scanned string does not contain an Integer literal with optional leading white space.

Extends from Modelica.​Icons.​Function (Icon for functions).

Inputs

TypeNameDescription
StringstringString to be scanned
IntegerstartIndexStart scanning of string at character startIndex
Booleanunsigned= true, if Integer token shall not start with a sign
StringmessageMessage used in error message if scan is not successful

Outputs

TypeNameDescription
IntegernumberValue of Integer number
IntegernextIndexIndex of character after the found number

Function Modelica.​Utilities.​Strings.​scanBoolean
Scan for the next Boolean number and trigger an assert if not present

Information

Syntax

             number = Strings.scanBoolean(string);
(number, nextIndex) = Strings.scanBoolean(string, startIndex=1, message="");

Description

Function scanBoolean scans the string starting at index "startIndex", checks whether the next token is a Boolean literal (i.e., is either the string "false" or "true", if converted to lower case letters) and returns its value as a Boolean number, as well as the index directly after the Boolean number. An assert is triggered, if the scanned string does not contain a Boolean literal with optional leading white space.

Extends from Modelica.​Icons.​Function (Icon for functions).

Inputs

TypeNameDescription
StringstringString to be scanned
IntegerstartIndexStart scanning of string at character startIndex
StringmessageMessage used in error message if scan is not successful

Outputs

TypeNameDescription
BooleannumberValue of Boolean
IntegernextIndexIndex of character after the found number

Function Modelica.​Utilities.​Strings.​scanString
Scan for the next Modelica string and trigger an assert if not present

Information

Syntax

             string2 = Strings.scanString(string);
(string2, nextIndex) = Strings.scanString(string, startIndex=1, message="");

Description

Function scanString scans the string starting at index "startIndex", checks whether the next token is a String literal and returns its value as a String, as well as the index directly after the String. An assert is triggered, if the scanned string does not contain a String literal with optional leading white space.

Extends from Modelica.​Icons.​Function (Icon for functions).

Inputs

TypeNameDescription
StringstringString to be scanned
IntegerstartIndexStart scanning of string at character startIndex
StringmessageMessage used in error message if scan is not successful

Outputs

TypeNameDescription
StringresultValue of string
IntegernextIndexIndex of character after the found string

Function Modelica.​Utilities.​Strings.​scanIdentifier
Scan for the next Identifier and trigger an assert if not present

Information

Syntax

             identifier = Strings.scanIdentifier(string);
(identifier, nextIndex) = Strings.scanIdentifier(string, startIndex=1, message="");

Description

Function scanIdentifier scans the string starting at index "startIndex", checks whether the next token is an Identifier and returns its value as a string, as well as the index directly after the Identifier. An assert is triggered, if the scanned string does not contain an Identifier with optional leading white space.

Extends from Modelica.​Icons.​Function (Icon for functions).

Inputs

TypeNameDescription
StringstringString to be scanned
IntegerstartIndexStart scanning of identifier at character startIndex
StringmessageMessage used in error message if scan is not successful

Outputs

TypeNameDescription
StringidentifierValue of Identifier
IntegernextIndexIndex of character after the found identifier

Function Modelica.​Utilities.​Strings.​scanDelimiter
Scan for the next delimiter and trigger an assert if not present

Information

Syntax

             delimiter = Strings.scanDelimiter(string);
(delimiter, nextIndex) = Strings.scanDelimiter(string, startIndex=1,
                                 requiredDelimiters={","}, message="");

Description

Function scanDelimiter scans the string starting at index "startIndex", checks whether the next token is a delimiter string and returns its value as a string, as well as the index directly after the delimiter. An assert is triggered, if the scanned string does not contain a delimiter out of the list of requiredDelimiters. Input argument requiredDelimiters is a vector of strings. The elements may have any length, including length 0. If an element of the requiredDelimiters is zero, white space is treated as delimiter. The function returns delimiter="" and nextIndex is the index of the first non white space character.

Extends from Modelica.​Icons.​Function (Icon for functions).

Inputs

TypeNameDescription
StringstringString to be scanned
IntegerstartIndexStart scanning of delimiters at character startIndex
StringrequiredDelimiters[:]Delimiters that are searched
StringmessageMessage used in error message if scan is not successful

Outputs

TypeNameDescription
StringdelimiterFound delimiter
IntegernextIndexIndex of character after the found delimiter

Function Modelica.​Utilities.​Strings.​scanNoToken
Scan string and check that it contains no more token

Information

Syntax

Strings.scanNoToken(string, startIndex=1, message="");

Description

Function scanNoToken scans the string starting at index "startIndex" and checks whether there is no more token in the string. An assert is triggered if this is not the case, using the "message" argument as additional explanation in the error text.

Extends from Modelica.​Icons.​Function (Icon for functions).

Inputs

TypeNameDescription
StringstringString to be scanned
IntegerstartIndexStart scanning of string at character startIndex
StringmessageMessage used in error message if scan is not successful

Function Modelica.​Utilities.​Strings.​syntaxError
Print an error message, a string and the index at which scanning detected an error

Information

Syntax

Strings.syntaxError(string, index, message);

Description

Function syntaxError prints an error message in the following form:

   Syntax error at column <index> of
   <string>
       ^       // shows character that is wrong
   <message>

where the strings within <..> are the actual values of the input arguments of the function.

If the given string is too long, only a relevant part of the string is printed.

Extends from Modelica.​Icons.​Function (Icon for functions).

Inputs

TypeNameDescription
StringstringString that has an error at position index
IntegerindexIndex of string at which scanning detected an error
StringmessageString printed at end of error message