Grammar of arithmetic expressions.

SUM     ::= PRODUCT | SUM [+-] PRODUCT
PRODUCT ::= FACTOR | PRODUCT [*/] FACTOR
FACTOR  ::= NUMBER | [(] NUMBER [)]
NUMBER  ::= [0-9] | [0-9] NUMBER

Example

pparse arithG SUM "1+2*3"

Ambiguous grammar of arithmetic expressions.

SUM     ::= PRODUCT | SUM [+-] SUM
PRODUCT ::= FACTOR | PRODUCT [*/] PRODUCT
FACTOR  ::= NUMBER | [(] NUMBER [)]
NUMBER  ::= [0-9] | [0-9] NUMBER

Example

pparse aArithG SUM "1+2-3"

Grammar of lambda expressions.

LAMBDA ::= VAR | [\] VAR [.] LAMBDA | [(] LAMBDA [)] LAMBDA
VAR    ::= [a-z]

Example

pparse lambdaG LAMBDA "\\x.x"
pparse lambdaG LAMBDA "(\\x.(x)x)\\x.(x)x"

ML-like syntax.

TERM ::= ATOMS
     | "fun" VAR "->" TERM
     | "let" VAR "=" TERM "in" TERM
     | "if" TERM "then" TERM
     | "if" TERM "then" TERM "else" TERM
ATOMS ::= ATOM | ATOMS ATOM
ATOM ::= VAR
     | "(" TERM ")"
VAR ::= "a" | "b" | "c" | ...

Example

Featuring the if-then-else ambiguity.

pparse mlG TERM (words "if a then if b then c else d")

JSON grammar.

JSON   ::= "null" | "true" | "false" | (number) | (string) | "{" OBJECT "}" | "[" ARRAY "]"
OBJECT ::= (string) ":" JSON | (string) ":" JSON "," OBJECT
ARRAY ::= JSON | JSON "," ARRAY

Example

pparse jsonG JSON (words "{ \"key\" : \"answer\" , \"contents\" : 42 }")

Non-terminals for arithmetic expressions.

Non-terminals for lambda expressions.

Non-terminals for an ML-like language.

Non-terminals for JSON.

Basic character classes.

Membership function for character classes.