71 lines
1.5 KiB
Go
71 lines
1.5 KiB
Go
/*
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Serene --- Yet an other Lisp
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Copyright (c) 2020 Sameer Rahmani <lxsameer@gnu.org>
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 2 of the License.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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package core
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import "fmt"
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type IScope interface {
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Lookup(rt *Runtime, k string) *Binding
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Insert(k string, v IExpr, public bool)
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}
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type Binding struct {
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Value IExpr
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Public bool
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}
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type Scope struct {
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bindings map[string]Binding
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parent *Scope
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}
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func (s *Scope) Lookup(rt *Runtime, k string) *Binding {
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if rt.IsDebugMode() {
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fmt.Printf("[DEBUG] Looking up '%s'\n", k)
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}
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v, ok := s.bindings[k]
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if ok {
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return &v
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}
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if s.parent != nil {
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return s.parent.Lookup(rt, k)
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}
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builtin := rt.LookupBuiltin(k)
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if builtin != nil {
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return &Binding{builtin, true}
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}
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return nil
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}
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func (s *Scope) Insert(k string, v IExpr, public bool) {
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s.bindings[k] = Binding{Value: v, Public: public}
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}
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func MakeScope(parent *Scope) *Scope {
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return &Scope{
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parent: parent,
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bindings: map[string]Binding{},
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}
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}
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