embed stdmod in binary

Makefile

@@ -28,6 +28,7 @@ gotest: clean $(BIN)
 .PHONY: sbtest
 sbtest: clean $(BIN)
 	ls -1 tests/*.sb | xargs -L 1 ./shiba
+	ls -1 tests/**/*.sb | xargs -L 1 ./shiba
 
 .PHONY: clean
 clean:

mod.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"container/list"
+	"embed"
 	"os"
 	"path/filepath"
 	"strings"
@@ -62,6 +63,9 @@ type module struct {
 	funcscopes *list.List
 }
 
+//go:embed std
+var stdmodfs embed.FS
+
 func newmodule(modname string) (*module, error) {
 	dir, mod := filepath.Split(modname)
 
@@ -84,6 +88,26 @@ func newmodule(modname string) (*module, error) {
 	}, nil
 }
 
+func newstdmodule(mod string) (*module, error) {
+	file := modtofile(mod)
+
+	bs, err := stdmodfs.ReadFile(filepath.Join("std/", file))
+	if err != nil {
+		return nil, err
+	}
+
+	content := []rune(string(bs))
+
+	return &module{
+		name:       mod,
+		filename:   file,
+		directory:  "std",
+		content:    content,
+		globscope:  newscope(),
+		funcscopes: list.New(),
+	}, nil
+}
+
 func (m *module) createfuncscope() {
 	m.funcscopes.PushBack(newscope())
 }

process.go

@@ -633,16 +633,14 @@ func procFuncall(mod *module, n *ndFuncall) (procResult, shibaErr) {
 }
 
 func procImport(mod *module, n *ndImport) (procResult, shibaErr) {
-	modname := ""
-	if isstdmod(n.target) {
-		modname = filepath.Join(stdmoddir(), n.target)
-	} else {
-		modname = filepath.Join(mod.directory, n.target)
-	}
-
-	m, err := newmodule(modname)
+	// first, try to import user-defined module
+	m, err := newmodule(filepath.Join(mod.directory, n.target))
 	if err != nil {
-		return nil, &errSimple{msg: fmt.Sprintf("cannot import %s: %s", n.target, err), l: n.token().loc}
+		// if err, try to import std module
+		m, err = newstdmodule(n.target)
+		if err != nil {
+			return nil, &errSimple{msg: fmt.Sprintf("cannot import %s: %s", n.target, err), l: n.token().loc}
+		}
 	}
 
 	if err := runmod(m); err != nil {

tests/import_order/import.sb

@@ -0,0 +1,11 @@
+import ../assert
+
+as = assert.assert
+
+# os is defined in stdmod, but
+# the ./os.sb is read
+import os
+
+as(1, os.v)
+
+print("import_order test succeeded")

tests/import_order/os.sb

@@ -0,0 +1 @@
+v = 1