|  |  4.21.2 string expressions 
A string expression is:
 
a sequence of characters between two unescaped quotes (")
an identifier of type string
a function returning string
a substring (using the bracket operator)
a type cast to string (see  string type cast)
string expressions combined by the operation +. 
Example:
 |  | // string_expression[start, length] : a substring
// (possibly filled up with blanks)
// the substring of s starting at position 2
// with a length of 4
string s="123456";
s[2,4];
==> 2345
"abcd"[2,2];
==> bc
// string_expression[position] : a character from a string
s[3];
==> 3
// string_expression[position..position] :
// a substring starting at the first position up to the second
// given position
s[2..4];
==> 2 3 4
// a function returning a string
typeof(s);
==> string
 | 
 
See  Type conversion and casting
 
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