Syntactic errors: 11
Costabs-CoFloCo-TypedNorms/flatten.abs:8:17:mismatched input 'f' expecting ')'
def B comp<A,B>(f, g)(A x) = f(g(x));
----------------^
Costabs-CoFloCo-TypedNorms/flatten.abs:18:30:mismatched input '=>' expecting {')', '-', '*', '/', '%', '+', '<=', '>=', '<', '>', '&&', '||', '==', '!='}
    Leaf(x) => ((List<A> xs) => cons(x,xs)); // Error: Higher-order constructs are not supported!
-----------------------------^
Costabs-CoFloCo-TypedNorms/flatten.abs:18:37:missing '=>' at '('
    Leaf(x) => ((List<A> xs) => cons(x,xs)); // Error: Higher-order constructs are not supported!
------------------------------------^
Costabs-CoFloCo-TypedNorms/flatten.abs:18:39:mismatched input ',' expecting {')', '-', '*', '/', '%', '+', '<=', '>=', '<', '>', '&&', '||', '==', '!='}
    Leaf(x) => ((List<A> xs) => cons(x,xs)); // Error: Higher-order constructs are not supported!
--------------------------------------^
Costabs-CoFloCo-TypedNorms/flatten.abs:18:43:extraneous input ')' expecting {';', '-', '*', '/', '%', '+', '<=', '>=', '<', '>', '&&', '||', '==', '!='}
    Leaf(x) => ((List<A> xs) => cons(x,xs)); // Error: Higher-order constructs are not supported!
------------------------------------------^
Costabs-CoFloCo-TypedNorms/flatten.abs:19:32:mismatched input '=>' expecting {')', '-', '*', '/', '%', '+', '<=', '>=', '<', '>', '&&', '||', '==', '!='}
    Node(t1,t2) => (List<A> xs => comp(walk(t1), walk(t2))(xs));
-------------------------------^
Costabs-CoFloCo-TypedNorms/flatten.abs:19:39:missing '=>' at '('
    Node(t1,t2) => (List<A> xs => comp(walk(t1), walk(t2))(xs));
--------------------------------------^
Costabs-CoFloCo-TypedNorms/flatten.abs:19:48:mismatched input ',' expecting {')', '-', '*', '/', '%', '+', '<=', '>=', '<', '>', '&&', '||', '==', '!='}
    Node(t1,t2) => (List<A> xs => comp(walk(t1), walk(t2))(xs));
-----------------------------------------------^
Costabs-CoFloCo-TypedNorms/flatten.abs:19:54:missing '=>' at '('
    Node(t1,t2) => (List<A> xs => comp(walk(t1), walk(t2))(xs));
-----------------------------------------------------^
Costabs-CoFloCo-TypedNorms/flatten.abs:19:58:mismatched input ')' expecting {';', '-', '*', '/', '%', '+', '<=', '>=', '<', '>', '&&', '||', '==', '!='}
    Node(t1,t2) => (List<A> xs => comp(walk(t1), walk(t2))(xs));
---------------------------------------------------------^
Costabs-CoFloCo-TypedNorms/flatten.abs:19:62:mismatched input ')' expecting '=>'
    Node(t1,t2) => (List<A> xs => comp(walk(t1), walk(t2))(xs));
-------------------------------------------------------------^

Compilation failed with syntax errors.