added type casts

stdlib/bool.go

@@ -23,6 +23,28 @@ import (
     "gitlab.com/whom/shs/ast"
 )
 
+func bool_cast(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
+    in = in.Eval(ft, vt, false)
+    if in.Tag == ast.LIST || in.Tag == ast.NUMBER {
+        log.Log(log.ERR,
+            "only strings successfully cast to bool",
+            "bool cast")
+        return nil
+    }
+
+    body := in.Value()
+    if body != ast.TRUE && body != ast.FALSE {
+        log.Log(log.ERR,
+            "cast to bool failed",
+            "bool cast")
+        return nil
+    }
+
+    res := &ast.Token{ Tag: ast.BOOL }
+    res.Set(body)
+    return res
+}
+
 func not(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
     in = in.Eval(ft, vt, false)