I'm preparing a class on the modified BNF notation that python uses. I.e.,
Each rule begins with a name (which is the name defined by the rule) and ::=. A vertical bar (
|) is used to separate alternatives; it is the least binding operator in this notation. A star (*) means zero or more repetitions of the preceding item; likewise, a plus (+) means one or more repetitions, and a phrase enclosed in square brackets ([ ]) means zero or one occurrences (in other words, the enclosed phrase is optional). The*and+operators bind as tightly as possible; parentheses are used for grouping. Source
For this class, I'm not allowed to assume the students have prior knowledge in CS. Thus I must rely on concepts from general knowledge to provide examples in the use of BNF.
In other words, I can't use something like
longstringitem ::= longstringchar | stringescapeseq,
I must use something like this instead:
digit ::= 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9
"a digit is defined as either 0 or 1 or 2 or 3 or 4 or 5 or 6 or 7 or 8 or 9"
What are some non-CS concepts that can be used to illustrate the * sign (zero or more repetitions of the preceding item,) the + sign (one or more repetitions,) the phrase enclosed in [] (zero or one occurrences) and the () (used for grouping) from the BNF notation?