From 4dc8a922c9c802d4a3605d56da9eb62c741da94f Mon Sep 17 00:00:00 2001
From: HAYAMA_Kaoru <iyahaya@nifty.com>
Date: Tue, 3 Dec 2024 14:28:00 +0900
Subject: [PATCH] Implement `(setenv KEY VAL)`

---
 global.go | 19 +++++++++++++++++++
 main.go   |  1 +
 2 files changed, 20 insertions(+)

diff --git a/global.go b/global.go
index 57269db..f253824 100644
--- a/global.go
+++ b/global.go
@@ -190,3 +190,22 @@ func (g *Global) getenv(ctx context.Context, w *gmnlisp.World, arg gmnlisp.Node)
 	}
 	return gmnlisp.String(value), nil
 }
+
+func (g *Global) setenv(ctx context.Context, w *gmnlisp.World, __key, __val gmnlisp.Node) (gmnlisp.Node, error) {
+	_key, err := gmnlisp.ExpectClass[gmnlisp.String](ctx, w, __key)
+	if err != nil {
+		return nil, err
+	}
+	key := string(_key)
+
+	if gmnlisp.IsNull(__val) {
+		return gmnlisp.Null, os.Unsetenv(key)
+	}
+	_val, err := gmnlisp.ExpectClass[gmnlisp.String](ctx, w, __val)
+	if err != nil {
+		return nil, err
+	}
+	val := string(_val)
+
+	return gmnlisp.Null, os.Setenv(key, val)
+}
diff --git a/main.go b/main.go
index 68735c9..7254ffa 100644
--- a/main.go
+++ b/main.go
@@ -38,6 +38,7 @@ func mains(args []string) error {
 			gmnlisp.NewSymbol("expect*"): gmnlisp.SpecialF(g.expectX),
 			gmnlisp.NewSymbol("expect"):  gmnlisp.SpecialF(g.expect),
 			gmnlisp.NewSymbol("getenv"):  gmnlisp.Function1(g.getenv),
+			gmnlisp.NewSymbol("setenv"):  gmnlisp.Function2(g.setenv),
 		})
 
 	if len(args) <= 0 {