A character literal is any string of characters enclosed in quotation marks as shown in the following example:
‘This is a character string.’
“This is a character string, too.”
For convenience, you can enter character literals without the delimiting quotation marks; however, quotation marks are required in some situations. The rules for using quotation marks are described in Quotation Marks.
Valid and Invalid Literals
The following are examples of valid literals:
‘abc’
Is a character string.
‘ab”C’
Is a character string.
”
Is a null string.
3.14159
Is a number literal.
9
Is a number literal.
‘10.99’
Is a character string.
‘John\’s toy boat’
Is a character string.
‘ABCd_EfG’
Is a character string.
‘1234A’
Is a character string.
The following are examples of invalid literals:
1 23
Spaces are not permitted in number literals.
$10.99
Periods are not permitted in an unquoted character string, and the dollar sign is not permitted in a number literal.
‘John’s toy boat’
‘John’ is a valid character string, but the rest of the line is invalid.