diff --git a/anselme/ast/ArgumentTuple.lua b/anselme/ast/ArgumentTuple.lua
index 42d57bf..66b7803 100644
--- a/anselme/ast/ArgumentTuple.lua
+++ b/anselme/ast/ArgumentTuple.lua
@@ -35,7 +35,6 @@ ArgumentTuple = ast.abstract.Node {
 		assert(not self.assignment)
 		self.arity = self.arity + 1
 		self.assignment = val
-		self.format_priority = operator_priority["_=_"]
 	end,
 
 	_format = function(self, state, priority, ...)
@@ -56,6 +55,13 @@ ArgumentTuple = ast.abstract.Node {
 		end
 		return s
 	end,
+	_format_priority = function(self)
+		if self.assignment then
+			return operator_priority["_=_"]
+		else
+			return math.huge
+		end
+	end,
 
 	traverse = function(self, fn, ...)
 		for i=1, self.arity do
diff --git a/anselme/ast/Assignment.lua b/anselme/ast/Assignment.lua
index faeb5bf..b4b09a9 100644
--- a/anselme/ast/Assignment.lua
+++ b/anselme/ast/Assignment.lua
@@ -8,7 +8,6 @@ local Assignment = ast.abstract.Node {
 
 	identifier = nil,
 	expression = nil,
-	format_priority = operator_priority["_=_"],
 
 	init = function(self, identifier, expression)
 		self.identifier = identifier
@@ -18,6 +17,9 @@ local Assignment = ast.abstract.Node {
 	_format = function(self, ...)
 		return self.identifier:format(...).." = "..self.expression:format_right(...)
 	end,
+	_format_priority = function(self)
+		return operator_priority["_=_"]
+	end,
 
 	traverse = function(self, fn, ...)
 		fn(self.identifier, ...)
diff --git a/anselme/ast/Call.lua b/anselme/ast/Call.lua
index 8b6f918..090a51d 100644
--- a/anselme/ast/Call.lua
+++ b/anselme/ast/Call.lua
@@ -19,26 +19,10 @@ Call = ast.abstract.Node {
 
 	func = nil,
 	arguments = nil, -- ArgumentTuple
-	format_priority = infix["_!"], -- often overwritten in :init
 
 	init = function(self, func, arguments)
 		self.func = func
 		self.arguments = arguments
-
-		-- get priority: operators
-		if Identifier:is(self.func) then
-			local name, arity = self.func.name, self.arguments.arity
-			if infix[name] and arity == 2 then
-				self.format_priority = infix[name]
-			elseif prefix[name] and arity == 1 then
-				self.format_priority = prefix[name]
-			elseif suffix[name] and arity == 1 then
-				self.format_priority = suffix[name]
-			end
-		end
-		if self.arguments.assignment then
-			self.format_priority = operator_priority["_=_"]
-		end
 	end,
 
 	_format = function(self, ...)
@@ -66,6 +50,22 @@ Call = ast.abstract.Node {
 			return self.func:format(...)..self.arguments:format(...) -- no need for format_right, we already handle the assignment priority here
 		end
 	end,
+	_format_priority = function(self)
+		if Identifier:is(self.func) then
+			local name, arity = self.func.name, self.arguments.arity
+			if infix[name] and arity == 2 then
+				return infix[name]
+			elseif prefix[name] and arity == 1 then
+				return prefix[name]
+			elseif suffix[name] and arity == 1 then
+				return suffix[name]
+			end
+		end
+		if self.arguments.assignment then
+			return operator_priority["_=_"]
+		end
+		return operator_priority["_!"]
+	end,
 
 	traverse = function(self, fn, ...)
 		fn(self.func, ...)
diff --git a/anselme/ast/Choice.lua b/anselme/ast/Choice.lua
index 73e6eb1..c1bedd3 100644
--- a/anselme/ast/Choice.lua
+++ b/anselme/ast/Choice.lua
@@ -9,7 +9,6 @@ Choice = ast.abstract.Runtime {
 
 	text = nil,
 	func = nil,
-	format_priority = operator_priority["_|>_"],
 
 	init = function(self, text, func)
 		self.text = text
@@ -24,6 +23,9 @@ Choice = ast.abstract.Runtime {
 	_format = function(self, ...)
 		return ("%s |> %s"):format(self.text:format(...), self.func:format_right(...))
 	end,
+	_format_priority = function(self)
+		return operator_priority["_|>_"]
+	end,
 
 	build_event_data = function(self, state, event_buffer)
 		local l = {
diff --git a/anselme/ast/Definition.lua b/anselme/ast/Definition.lua
index abd0dc9..8d33951 100644
--- a/anselme/ast/Definition.lua
+++ b/anselme/ast/Definition.lua
@@ -8,7 +8,6 @@ local Definition = ast.abstract.Node {
 
 	symbol = nil,
 	expression = nil,
-	format_priority = operator_priority["_=_"],
 
 	init = function(self, symbol, expression)
 		self.symbol = symbol
@@ -18,6 +17,9 @@ local Definition = ast.abstract.Node {
 	_format = function(self, ...)
 		return self.symbol:format(...).." = "..self.expression:format_right(...)
 	end,
+	_format_priority = function(self)
+		return operator_priority["_=_"]
+	end,
 
 	traverse = function(self, fn, ...)
 		fn(self.symbol, ...)
diff --git a/anselme/ast/Environment.lua b/anselme/ast/Environment.lua
index cf8b36f..4f36722 100644
--- a/anselme/ast/Environment.lua
+++ b/anselme/ast/Environment.lua
@@ -9,7 +9,6 @@ local VariableMetadata = ast.abstract.Runtime {
 
 	symbol = nil,
 	branched = nil,
-	format_priority = operator_priority["_=_"],
 
 	init = function(self, state, symbol, value)
 		self.symbol = symbol
@@ -45,6 +44,10 @@ local VariableMetadata = ast.abstract.Runtime {
 	_format = function(self, ...)
 		return ("%s=%s"):format(self.symbol:format(...), self.branched:format(...))
 	end,
+	_format_priority = function(self)
+		return operator_priority["_=_"]
+	end,
+
 	traverse = function(self, fn, ...)
 		fn(self.symbol, ...)
 		fn(self.branched, ...)
diff --git a/anselme/ast/Function.lua b/anselme/ast/Function.lua
index 6d66bbb..cfed1e2 100644
--- a/anselme/ast/Function.lua
+++ b/anselme/ast/Function.lua
@@ -12,7 +12,6 @@ Function = Overloadable {
 
 	parameters = nil, -- ParameterTuple
 	expression = nil,
-	format_priority = operator_priority["$_"],
 
 	exports = nil, -- { [sym] = exp, ... }, exctracted from expression during :prepare
 
@@ -29,6 +28,9 @@ Function = Overloadable {
 			return "$"..self.parameters:format(...).." "..self.expression:format_right(...)
 		end
 	end,
+	_format_priority = function(self)
+		return operator_priority["$_"]
+	end,
 
 	traverse = function(self, fn, ...)
 		fn(self.parameters, ...)
diff --git a/anselme/ast/FunctionParameter.lua b/anselme/ast/FunctionParameter.lua
index b71977c..5cc4fd8 100644
--- a/anselme/ast/FunctionParameter.lua
+++ b/anselme/ast/FunctionParameter.lua
@@ -13,11 +13,6 @@ FunctionParameter = ast.abstract.Node {
 		self.identifier = identifier
 		self.default = default
 		self.type_check = type_check
-		if default then
-			self.format_priority = operator_priority["_=_"]
-		elseif type_check then -- type_check has higher prio than assignment in any case
-			self.format_priority = operator_priority["_::_"]
-		end
 	end,
 
 	_format = function(self, state, prio, ...)
@@ -30,6 +25,15 @@ FunctionParameter = ast.abstract.Node {
 		end
 		return s
 	end,
+	_format_priority = function(self)
+		if self.default then
+			return operator_priority["_=_"]
+		elseif self.type_check then -- type_check has higher prio than assignment in any case
+			return operator_priority["_::_"]
+		else
+			return math.huge
+		end
+	end,
 
 	traverse = function(self, fn, ...)
 		fn(self.identifier, ...)
diff --git a/anselme/ast/List.lua b/anselme/ast/List.lua
index 6c232a0..bdcc923 100644
--- a/anselme/ast/List.lua
+++ b/anselme/ast/List.lua
@@ -7,8 +7,6 @@ local List
 List = ast.abstract.Runtime {
 	type = "list",
 
-	format_priority = operator_priority["*_"],
-
 	-- note: yeah technically this isn't mutable, only .branched is
 
 	-- note: this a Branched of Tuple, and we *will* forcefully mutate the tuples, so make sure to not disseminate any reference to them outside the List
@@ -23,6 +21,9 @@ List = ast.abstract.Runtime {
 	_format = function(self, ...)
 		return "*"..self.branched:format_right(...)
 	end,
+	_format_priority = function(self)
+		return operator_priority["*_"]
+	end,
 
 	traverse = function(self, fn, ...)
 		fn(self.branched, ...)
diff --git a/anselme/ast/LuaFunction.lua b/anselme/ast/LuaFunction.lua
index 870b00f..5bdfd11 100644
--- a/anselme/ast/LuaFunction.lua
+++ b/anselme/ast/LuaFunction.lua
@@ -10,7 +10,6 @@ LuaFunction = ast.abstract.Runtime(Overloadable) {
 
 	parameters = nil, -- ParameterTuple
 	func = nil, -- lua function
-	format_priority = operator_priority["$_"],
 
 	init = function(self, parameters, func)
 		self.parameters = parameters
@@ -28,6 +27,9 @@ LuaFunction = ast.abstract.Runtime(Overloadable) {
 			return "$"..self.parameters:format(...).." <lua function>"
 		end
 	end,
+	_format_priority = function(self)
+		return operator_priority["$_"]
+	end,
 
 	compatible_with_arguments = function(self, state, args)
 		return args:match_parameter_tuple(state, self.parameters)
diff --git a/anselme/ast/Pair.lua b/anselme/ast/Pair.lua
index ee87477..c4fa0a4 100644
--- a/anselme/ast/Pair.lua
+++ b/anselme/ast/Pair.lua
@@ -7,7 +7,6 @@ return ast.abstract.Runtime {
 
 	name = nil,
 	value = nil,
-	format_priority = operator_priority["_:_"],
 
 	init = function(self, name, value)
 		self.name = name
@@ -22,4 +21,7 @@ return ast.abstract.Runtime {
 	_format = function(self, ...)
 		return ("%s:%s"):format(self.name:format(...), self.value:format(...))
 	end,
+	_format_priority = function(self)
+		return operator_priority["_:_"]
+	end,
 }
diff --git a/anselme/ast/ParameterTuple.lua b/anselme/ast/ParameterTuple.lua
index 258859b..2c771e0 100644
--- a/anselme/ast/ParameterTuple.lua
+++ b/anselme/ast/ParameterTuple.lua
@@ -27,7 +27,6 @@ ParameterTuple = ast.abstract.Node {
 	insert_assignment = function(self, val) -- only for construction
 		self:insert(val)
 		self.assignment = true
-		self.format_priority = operator_priority["_=_"]
 	end,
 
 	_format = function(self, state, prio, ...)
@@ -43,6 +42,12 @@ ParameterTuple = ast.abstract.Node {
 		end
 		return s
 	end,
+	_format_priority = function(self)
+		if self.assignment then
+			return operator_priority["_=_"]
+		end
+		return math.huge
+	end,
 
 	traverse = function(self, fn, ...)
 		for _, e in ipairs(self.list) do
diff --git a/anselme/ast/PartialScope.lua b/anselme/ast/PartialScope.lua
index a412dc1..eb1976b 100644
--- a/anselme/ast/PartialScope.lua
+++ b/anselme/ast/PartialScope.lua
@@ -18,7 +18,6 @@ PartialScope = ast.abstract.Node {
 		self.expression = expression
 		self.definitions = {}
 		self._identifiers = {}
-		self.format_priority = self.expression.format_priority
 	end,
 	define = function(self, symbol, value) -- for construction only
 		assert(not self.definitions[symbol], ("%s already defined in partial layer"):format(symbol))
@@ -36,6 +35,9 @@ PartialScope = ast.abstract.Node {
 			return self.expression:format(state, priority, indentation, ...)
 		end
 	end,
+	_format_priority = function(self)
+		return self.expression:format_priority()
+	end,
 
 	traverse = function(self, fn, ...)
 		fn(self.expression, ...)
diff --git a/anselme/ast/Quote.lua b/anselme/ast/Quote.lua
index 7d1bb9e..b7c9d36 100644
--- a/anselme/ast/Quote.lua
+++ b/anselme/ast/Quote.lua
@@ -15,12 +15,14 @@ Quote = ast.abstract.Node {
 
 	init = function(self, expression)
 		self.expression = expression
-		self.format_priority = expression.format_priority
 	end,
 
 	_format = function(self, ...)
 		return self.expression:format(...) -- Quote is generated transparently by operators
 	end,
+	_format_priority = function(self)
+		return self.expression:format_priority()
+	end,
 
 	traverse = function(self, fn, ...)
 		fn(self.expression, ...)
diff --git a/anselme/ast/Return.lua b/anselme/ast/Return.lua
index 7d41cd0..4880aa0 100644
--- a/anselme/ast/Return.lua
+++ b/anselme/ast/Return.lua
@@ -7,7 +7,6 @@ Return = ast.abstract.Node {
 	type = "return",
 
 	expression = nil,
-	format_priority = operator_priority["@_"],
 
 	init = function(self, expression)
 		self.expression = expression
@@ -16,6 +15,9 @@ Return = ast.abstract.Node {
 	_format = function(self, ...)
 		return ("@%s"):format(self.expression:format_right(...))
 	end,
+	_format_priority = function(self)
+		return operator_priority["@_"]
+	end,
 
 	traverse = function(self, fn, ...)
 		fn(self.expression, ...)
diff --git a/anselme/ast/ReturnBoundary.lua b/anselme/ast/ReturnBoundary.lua
index 5bd5ba5..2740b44 100644
--- a/anselme/ast/ReturnBoundary.lua
+++ b/anselme/ast/ReturnBoundary.lua
@@ -10,12 +10,14 @@ local ReturnBoundary = ast.abstract.Node {
 
 	init = function(self, expression)
 		self.expression = expression
-		self.format_priority = self.expression.format_priority
 	end,
 
 	_format = function(self, ...)
 		return self.expression:format(...)
 	end,
+	_format_priority = function(self)
+		return self.expression:format_priority()
+	end,
 
 	traverse = function(self, fn, ...)
 		fn(self.expression, ...)
diff --git a/anselme/ast/StringInterpolation.lua b/anselme/ast/StringInterpolation.lua
index d9db8fc..4b80286 100644
--- a/anselme/ast/StringInterpolation.lua
+++ b/anselme/ast/StringInterpolation.lua
@@ -19,14 +19,14 @@ local StringInterpolation = ast.abstract.Node {
 		end
 	end,
 
-	_format = function(self, ...)
+	_format = function(self, state, prio, ...)
 		local l = {}
 		for _, e in ipairs(self.list) do
 			if String:is(e) then
 				local t = e.string:gsub("\\", "\\\\"):gsub("\n", "\\n"):gsub("\t", "\\t"):gsub("\"", "\\\"")
 				table.insert(l, t)
 			else
-				table.insert(l, ("{%s}"):format(e:format(...)))
+				table.insert(l, ("{%s}"):format(e:format(state, 0, ...)))
 			end
 		end
 		return ("\"%s\""):format(table.concat(l))
diff --git a/anselme/ast/Symbol.lua b/anselme/ast/Symbol.lua
index cbde7e6..189f626 100644
--- a/anselme/ast/Symbol.lua
+++ b/anselme/ast/Symbol.lua
@@ -24,9 +24,6 @@ Symbol = ast.abstract.Node {
 		self.alias = modifiers.alias
 		self.confined_to_branch = modifiers.confined_to_branch
 		self.exported = modifiers.exported
-		if self.type_check then
-			self.format_priority = operator_priority["_::_"]
-		end
 	end,
 
 	_eval = function(self, state)
@@ -66,6 +63,12 @@ Symbol = ast.abstract.Node {
 		end
 		return s
 	end,
+	_format_priority = function(self)
+		if self.type_check then
+			return operator_priority["_::_"]
+		end
+		return math.huge
+	end,
 
 	to_lua = function(self, state)
 		return self.string
diff --git a/anselme/ast/Table.lua b/anselme/ast/Table.lua
index 4bbfceb..e3e2056 100644
--- a/anselme/ast/Table.lua
+++ b/anselme/ast/Table.lua
@@ -7,8 +7,6 @@ local Table
 Table = ast.abstract.Runtime {
 	type = "table",
 
-	format_priority = operator_priority["*_"],
-
 	-- note: technically this isn't mutable, only .branched is
 
 	-- note: this a Branched of Struct, and we *will* forcefully mutate the tuples, so make sure to not disseminate any reference to them outside the Table
@@ -23,6 +21,9 @@ Table = ast.abstract.Runtime {
 	_format = function(self, ...)
 		return "*"..self.branched:format_right(...)
 	end,
+	_format_priority = function(self)
+		return operator_priority["*_"]
+	end,
 
 	traverse = function(self, fn, ...)
 		fn(self.branched, ...)
diff --git a/anselme/ast/TextInterpolation.lua b/anselme/ast/TextInterpolation.lua
index 652e0c6..b93d2a5 100644
--- a/anselme/ast/TextInterpolation.lua
+++ b/anselme/ast/TextInterpolation.lua
@@ -21,14 +21,14 @@ local TextInterpolation = ast.abstract.Node {
 		end
 	end,
 
-	_format = function(self, ...)
+	_format = function(self, state, prio, ...)
 		local l = {}
 		for _, e in ipairs(self.list) do
 			if String:is(e) then
 				local t = e.string:gsub("\\", "\\\\"):gsub("\n", "\\n"):gsub("\t", "\\t"):gsub("\"", "\\\"")
 				table.insert(l, t)
 			else
-				table.insert(l, ("{%s}"):format(e:format(...)))
+				table.insert(l, ("{%s}"):format(e:format(state, 0, ...)))
 			end
 		end
 		return ("| %s |"):format(table.concat(l))
diff --git a/anselme/ast/Translatable.lua b/anselme/ast/Translatable.lua
index 3794ab9..c4d6505 100644
--- a/anselme/ast/Translatable.lua
+++ b/anselme/ast/Translatable.lua
@@ -7,7 +7,6 @@ local translation_manager
 
 local Translatable = ast.abstract.Node {
 	type = "translatable",
-	format_priority = operator_priority["%_"],
 
 	expression = nil,
 
@@ -15,9 +14,6 @@ local Translatable = ast.abstract.Node {
 		self.expression = expression
 		self.context = ast.Struct:new()
 		self.context:set(String:new("source"), String:new(self.expression.source))
-		if TextInterpolation:is(self.expression) then
-			self.format_priority = expression.format_priority
-		end
 	end,
 
 	_format = function(self, ...)
@@ -27,6 +23,13 @@ local Translatable = ast.abstract.Node {
 			return "%"..self.expression:format_right(...)
 		end
 	end,
+	_format_priority = function(self)
+		if TextInterpolation:is(self.expression) then
+			return self.expression:format_priority()
+		else
+			return operator_priority["%_"]
+		end
+	end,
 
 	traverse = function(self, fn, ...)
 		fn(self.expression, ...)
diff --git a/anselme/ast/abstract/Node.lua b/anselme/ast/abstract/Node.lua
index 8ed7113..220f68e 100644
--- a/anselme/ast/abstract/Node.lua
+++ b/anselme/ast/abstract/Node.lua
@@ -257,9 +257,9 @@ Node = class {
 		indentation_level = indentation_level or 0
 		parent_priority = parent_priority or 0
 
-		local s = self:_format(state, self.format_priority, indentation_level)
+		local s = self:_format(state, self:format_priority(), indentation_level)
 
-		if self.format_priority < parent_priority then
+		if self:format_priority() < parent_priority then
 			s = ("(%s)"):format(s)
 		end
 
@@ -273,9 +273,9 @@ Node = class {
 		indentation_level = indentation_level or 0
 		parent_priority = parent_priority or 0
 
-		local s = self:_format(state, self.format_priority, indentation_level)
+		local s = self:_format(state, self:format_priority(), indentation_level)
 
-		if self.format_priority <= parent_priority then
+		if self:format_priority() <= parent_priority then
 			s = ("(%s)"):format(s)
 		end
 
@@ -288,9 +288,20 @@ Node = class {
 	_format = function(self, state, self_priority, identation)
 		error("format not implemented for "..self.type)
 	end,
-	-- priority of the node that will be used in :format to add eventually needed parentheses.
-	-- should not be modified after object construction!
-	format_priority = math.huge, -- by default, assumes primary node, i.e. never wrap in parentheses
+	-- compute the priority of the node that will be used in :format to add eventually needed parentheses.
+	-- should alwaus return the same value after object construction (will be cached anyway)
+	-- redefine _format_priority, not this function
+	format_priority = function(self)
+		if not self._format_priority_cache then
+			self._format_priority_cache = self:_format_priority()
+		end
+		return self._format_priority_cache
+	end,
+	-- redefine this to compute the priority, see :format_priority
+	_format_priority = function(self)
+		return math.huge -- by default, assumes primary node, i.e. never wrap in parentheses
+	end,
+	_format_priority_cache = nil, -- cached priority
 
 	-- return Lua value
 	-- this should probably be only called on a Node that is already evaluated
diff --git a/test/results/function separate variable from variants.ans b/test/results/function separate variable from variants.ans
index edafc7f..334c360 100644
--- a/test/results/function separate variable from variants.ans	
+++ b/test/results/function separate variable from variants.ans	
@@ -5,8 +5,8 @@
 	• (c::($(x) <lua function>), s::($(x) <lua function>)) = v: expected 3 arguments, received 2
 	• (c::($(x) <lua function>), s::($(x) <lua function>)): type check failure for parameter c in function (c::($(x) <lua function>), s::($(x) <lua function>))
 	↳ from test/tests/function separate variable from variants.ans:10:4 in call: f . "a"
-	↳ from test/tests/function separate variable from variants.ans:10:1 in text interpolation: | {(f . "a")} = 2 |
-	↳ from test/tests/function separate variable from variants.ans:10:1 in translatable: | {(f . "a")} = 2 |
+	↳ from test/tests/function separate variable from variants.ans:10:1 in text interpolation: | {f . "a"} = 2 |
+	↳ from test/tests/function separate variable from variants.ans:10:1 in translatable: | {f . "a"} = 2 |
 	↳ from ? in block: :f = ($() _)…
 --# saved #--
 {}
\ No newline at end of file