X-Git-Url: http://nitlanguage.org

diff --git a/src/modelize/modelize_property.nit b/src/modelize/modelize_property.nit
index aabe809..2ae2b59 100644
--- a/src/modelize/modelize_property.nit
+++ b/src/modelize/modelize_property.nit
@@ -1489,6 +1489,35 @@ redef class AAttrPropdef
 				abort
 			end
 			if cla != null then mtype = cla.mclass_type
+		else if nexpr isa AArrayExpr and nexpr.n_type == null and nexpr.n_exprs.not_empty then
+			# Non-empty arrays without an explicit type
+
+			var item_mtypes = new Set[MType]
+			var fails = false
+			for node in nexpr.n_exprs do
+				var item_mtype = infer_static_type(modelbuilder, node, mclassdef, mmodule, mreadpropdef)
+				if item_mtype == null then
+					fails = true
+				else
+					item_mtypes.add item_mtype
+				end
+			end
+
+			if fails then return null # Failed to infer some types
+
+			if item_mtypes.length > 1 then
+				modelbuilder.error(self, "Type Error: ambiguous array type {item_mtypes.join(" ")}")
+			end
+
+			mtype = mmodule.array_type(item_mtypes.first)
+		else if nexpr isa AUminusExpr and (nexpr.n_expr isa AIntegerExpr or nexpr.n_expr isa AFloatExpr) then
+			# The Int and Float unary - is defined in `kernel`, so this may
+			# result in an invalid behavior when using a custom kernel.
+			# A workaround is to declare the attribute static type.
+			# This is still very useful, especially to novice programmers.
+			mtype = infer_static_type(modelbuilder, nexpr.n_expr, mclassdef, mmodule, mreadpropdef)
+		else if nexpr isa AOnceExpr then
+			mtype = infer_static_type(modelbuilder, nexpr.n_expr, mclassdef, mmodule, mreadpropdef)
 		else
 			modelbuilder.error(self, "Error: untyped attribute `{mreadpropdef}`. Implicit typing allowed only for literals and new.")
 		end