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Grammar

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Can set of terminal be empty in a grammar?

Is epsilon (null string) counted as a terminal symbol?

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2 2 votes
Set of terminals should be non-empty and finite.
And epsilon is not a terminal symbol.
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Can set of terminal be empty in a grammar?

As per Ullman,

Terminal is a finite set of symbols that forms the string of the language being defined.

for a language,  L = { }, terminal set will be empty. 

Is epsilon (null string) counted as a terminal symbol?

The null string is not a terminal symbol. A terminal symbol is an element of the alphabet, but the empty string is not an element of the alphabet. Alphabet contain atomic symbols of length 1, but epsilon is of length 0.

 

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