Example:
package P
model M
extends A.B(a = 1.0, x(z = 2.0));
end M;
end P;
setExtendsModifierValue(P.M, A.B, x.y, $Code((start = 3.0))) =>
package P
model M
extends A.B(a = 1.0, x(z = 2.0, y(start = 3.0)));
end M;
end P;
function setExtendsModifierValue input TypeName className; input TypeName extendsName; input TypeName elementName; input ExpressionOrModification modifier; output Boolean success; end setExtendsModifierValue;