Example improved

Author: jig

README.md

@@ -86,44 +86,45 @@ You execute lisp from Go code and get results from it back to Go. Example from [
 
 ```go
 func ExampleEVAL() {
-	newEnv := env.NewEnv()
-
-	// Load required lisp libraries
-	for _, library := range []struct {
-		name string
-		load func(newEnv types.EnvType) error
-	}{
-		{"core mal", nscore.Load},
-		{"core mal with input", nscore.LoadInput},
-		{"command line args", nscore.LoadCmdLineArgs},
-		{"core mal extended", nscoreextended.Load},
-		{"assert", nsassert.Load},
-	} {
-		if err := library.load(newEnv); err != nil {
-			log.Fatalf("Library Load Error: %v", err)
-		}
-	}
-
-	// parse (READ) lisp code
-	ast, err := lisp.READ(`(+ 2 2)`, nil)
-	if err != nil {
-		log.Fatalf("READ error: %v", err)
-	}
-
-	// eval AST
-	result, err := lisp.EVAL(ast, newEnv, nil)
-	if err != nil {
-		log.Fatalf("EVAL error: %v", err)
-	}
-
-	// use result
-	if result.(int) != 4 {
-		log.Fatalf("Result check error: %v", err)
-	}
-
-	// optionally print resulting AST
-	fmt.Println(lisp.PRINT(result))
-	// Output: 4
+    newEnv := env.NewEnv()
+
+    // Load required lisp libraries
+    for _, library := range []struct {
+        name string
+        load func(newEnv types.EnvType) error
+    }{
+        {"core mal", nscore.Load},
+        {"core mal with input", nscore.LoadInput},
+        {"command line args", nscore.LoadCmdLineArgs},
+        {"concurrent", nsconcurrent.Load},
+        {"core mal extended", nscoreextended.Load},
+        {"system", nssystem.Load},
+    } {
+        if err := library.load(newEnv); err != nil {
+            log.Fatalf("Library Load Error %q: %v", library.name, err)
+        }
+    }
+
+    // parse (READ) lisp code
+    ast, err := lisp.READ(`(+ 2 2)`, nil, newEnv)
+    if err != nil {
+        log.Fatalf("READ error: %v", err)
+    }
+
+    // eval AST
+    result, err := lisp.EVAL(context.TODO(), ast, newEnv)
+    if err != nil {
+        log.Fatalf("EVAL error: %v", err)
+    }
+
+    // use result
+    if result.(int) != 4 {
+        log.Fatalf("Result check error: %v", err)
+    }
+
+    // optionally print resulting AST
+    fmt.Println(lisp.PRINT(result))
+    // Output: 4
 }
 ```
 

example/example_test.go

@@ -10,6 +10,7 @@ import (
 	"github.com/jig/lisp/lib/concurrent/nsconcurrent"
 	"github.com/jig/lisp/lib/core/nscore"
 	"github.com/jig/lisp/lib/coreextented/nscoreextended"
+	"github.com/jig/lisp/lib/system/nssystem"
 	"github.com/jig/lisp/types"
 )
 
@@ -26,6 +27,7 @@ func ExampleEVAL() {
 		{"command line args", nscore.LoadCmdLineArgs},
 		{"concurrent", nsconcurrent.Load},
 		{"core mal extended", nscoreextended.Load},
+		{"system", nssystem.Load},
 	} {
 		if err := library.load(newEnv); err != nil {
 			log.Fatalf("Library Load Error %q: %v", library.name, err)