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Multi-Function Calculator: `mfcalc'
Now that the basics of Bison have been discussed, it is time to move
on to a more advanced problem. The above calculators provided only five
functions, `+', `-', `*', `/' and `^'. It would be nice to have a
calculator that provides other mathematical functions such as `sin',
It is easy to add new operators to the infix calculator as long as
they are only single-character literals. The lexical analyzer `yylex'
passes back all non-number characters as tokens, so new grammar rules
suffice for adding a new operator. But we want something more
flexible: built-in functions whose syntax has this form:
At the same time, we will add memory to the calculator, by allowing you
to create named variables, store values in them, and use them later.
Here is a sample session with the multi-function calculator:
pi = 3.141592653589
alpha = beta1 = 2.3
Note that multiple assignment and nested function calls are
- Mfcalc DeclBison declarations for multi-function calculator.
- Mfcalc RulesGrammar rules for the calculator.
- Mfcalc SymtabSymbol table management subroutines.
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