val constant.Value // constant value; or nil (if not a constant)
}
-// A context represents the context within which an object is type-checked.
-type context struct {
+// An environment represents the environment within which an object is
+// type-checked.
+type environment struct {
decl *declInfo // package-level declaration whose init expression/function body is checked
scope *Scope // top-most scope for lookups
pos token.Pos // if valid, identifiers are looked up as if at position pos (used by Eval)
hasCallOrRecv bool // set if an expression contains a function call or channel receive operation
}
-// lookup looks up name in the current context and returns the matching object, or nil.
-func (ctxt *context) lookup(name string) Object {
- _, obj := ctxt.scope.LookupParent(name, ctxt.pos)
+// lookup looks up name in the current environment and returns the matching object, or nil.
+func (env *environment) lookup(name string) Object {
+ _, obj := env.scope.LookupParent(name, env.pos)
return obj
}
objPath []Object // path of object dependencies during type inference (for cycle reporting)
defTypes []*Named // defined types created during type checking, for final validation.
- // context within which the current object is type-checked
- // (valid only for the duration of type-checking a specific object)
- context
+ // environment within which the current object is type-checked (valid only
+ // for the duration of type-checking a specific object)
+ environment
// debugging
indent int // indentation for tracing
return s
}
-// objDecl type-checks the declaration of obj in its respective (file) context.
+// objDecl type-checks the declaration of obj in its respective (file) environment.
// For the meaning of def, see Checker.definedType, in typexpr.go.
func (check *Checker) objDecl(obj Object, def *Named) {
if trace && obj.Type() == nil {
unreachable()
}
- // save/restore current context and setup object context
- defer func(ctxt context) {
- check.context = ctxt
- }(check.context)
- check.context = context{
+ // save/restore current environment and set up object environment
+ defer func(env environment) {
+ check.environment = env
+ }(check.environment)
+ check.environment = environment{
scope: d.file,
}
// If we reach a generic type that is part of a cycle
// and we are in a type parameter list, we have a cycle
// through a type parameter list, which is invalid.
- if check.context.inTParamList && isGeneric(obj.typ) {
+ if check.environment.inTParamList && isGeneric(obj.typ) {
tparCycle = true
break loop
}
// function closures may appear inside a type parameter list but they
// cannot be generic, and their bodies are processed in delayed and
// sequential fashion. Note that with each new declaration, we save
- // the existing context and restore it when done; thus inTPList is
+ // the existing environment and restore it when done; thus inTPList is
// true exactly only when we are in a specific type parameter list.
assert(!check.inTParamList)
check.inTParamList = true
sig.scope.pos = body.Pos()
sig.scope.end = body.End()
- // save/restore current context and setup function context
+ // save/restore current environment and set up function environment
// (and use 0 indentation at function start)
- defer func(ctxt context, indent int) {
- check.context = ctxt
+ defer func(env environment, indent int) {
+ check.environment = env
check.indent = indent
- }(check.context, check.indent)
- check.context = context{
+ }(check.environment, check.indent)
+ check.environment = environment{
decl: decl,
scope: sig.scope,
iota: iota,