--- a/spec/util_dataforms_spec.lua	Mon Sep 03 17:45:30 2018 +0100
+++ b/spec/util_dataforms_spec.lua	Sat Sep 01 01:24:46 2018 +0200
@@ -386,5 +386,20 @@
 			assert.same(expect, data, "got back the same data");
 		end);
 	end);
+
+	describe("field 'var' property", function ()
+		it("works as expected", function ()
+			local f = dataforms.new {
+				{
+					var = "someprefix#the-field",
+					name = "the_field",
+					type = "text-single",
+				}
+			};
+			local x = f:form({the_field = "hello"});
+			assert.equal("someprefix#the-field", x:find"field@var");
+			assert.equal("hello", x:find"field/value#");
+		end);
+	end);
 end);
 

--- a/util/dataforms.lua	Mon Sep 03 17:45:30 2018 +0100
+++ b/util/dataforms.lua	Sat Sep 01 01:24:46 2018 +0200
@@ -42,7 +42,7 @@
 	for _, field in ipairs(layout) do
 		local field_type = field.type or "text-single";
 		-- Add field tag
-		form:tag("field", { type = field_type, var = field.name, label = formtype ~= "submit" and field.label or nil });
+		form:tag("field", { type = field_type, var = field.var or field.name, label = formtype ~= "submit" and field.label or nil });
 
 		if formtype ~= "submit" then
 			if field.desc then
@@ -150,7 +150,7 @@
 	for _, field in ipairs(layout) do
 		local tag;
 		for field_tag in stanza:childtags("field") do
-			if field.name == field_tag.attr.var then
+			if (field.var or field.name) == field_tag.attr.var then
 				tag = field_tag;
 				break;
 			end