grammar.txt

<All-formulas> ::= <Formula-names> = <Formulas> NEXTLINE <Rest-formulas>
<Formula-names> ::= IDENT <Formula-names-sub> //Names must be unique
<Formula-names-sub> ::= , <Formula-names> | E
<Rest-formulas> ::= <All-formulas> | E

<Formulas> ::= <Sum> <Next-formulaText>
<Next-formulaText> ::= , <Formulas> | E //count of formulas and formulas-names must match

<Sum> ::= <Mul> <Sum-sub>
<Sum-sub> ::= + <Sum> | - <Sum> | E

<Mul> ::= <Var> <Mul-sub>
<Var> ::= NUMBER | IDENT | ( <Sum> ) | - <Var> //all idents must be defined in functions
<Mul-sub> ::= * <Mul> | / <Mul> | E