. (pred y : bb)

. (pred y : bb * bb)

. (pred y : bb * bb)(a, b)

*** Error 4.18-4.20, expected further mixfix token: [":","!=","/=","<","<="]

*** Error 5.7, unexpected mixfix token: <

*** Error 6.3, unexpected mixfix token: #=

. exists1(predy :: bb)

. exists predy: bb . a

. exists! a: v . x

. exists! a: v . x

. exists! a: v . x

. forall a: v . x

. a if b

. def x

*** Error 15.4, unexpected mixfix token: #

*** Error 16.2, unexpected mixfix token: }

*** Error 16.3-16.9, not a formula: {} when [] else {}

. a /\ b /\ c

. a \/ b \/ c

. a => b

. a <=> b

. true

. false

. b in s

. a =e= b

. a = b

. a => b => c => d

. a if b if c if d

. a <=> b

. a /\ b if b \/ c if not c if def d

. m div n = r <=> (exists s: Nat . m = n * r + s /\ s < n)