String
Strings are a number of characters between two quotes. A string may itself contain a qoute, in which case this is indicated by a sequence of two quotes. Strings may contain newlines. The syntax for a string is:
<string> ::= ' { <char> | '' } '
<char> ::= any printable character at the keyboard
Examples
'this is a string'
'this is
also
a
string with a single quote '' and newlines'