func AbtabGrepMakeExpressionFilter(inp *AbtabURL, expr string) AbtabFilterFn {
var fset = token.NewFileSet()
w := eval.NewWorld()
InstallStandardLibrary(w)
var vars map[string]*eval.Variable = make(map[string]*eval.Variable, 1)
var empty = ""
var lnum int
v, _ := w.DefineVar("__LINE__", eval.TypeOfNative(lnum), eval.ToValue(lnum))
vars["__LINE__"] = v
for _, fname := range inp.Header {
v, _ := w.DefineVar(ScrubFieldNameForEval(fname), eval.TypeOfNative(empty), eval.ToValue(empty))
vars[fname] = v
}
return func(rec *Rec) (bool, error) {
// NB: this seems expensive, can we just re-assign to the internal var ref?
for idx, fname := range inp.Header {
var value = rec.Fields[idx]
vars[fname].Init = eval.ToValue(value)
}
//fmt.Fprintf(os.Stderr, "setting __LINE__=%d\n", rec.LineNum)
vars["__LINE__"].Init = eval.ToValue(int(rec.LineNum))
// NB: this seems expensive, can we compile once?
code, err := w.Compile(fset, expr)
if err != nil {
return false, err
}
v, err := code.Run()
if err != nil {
return false, err
}
if v.String() == "true" {
return true, nil
}
return false, nil
}
}
func main() {
flag.Parse()
w := eval.NewWorld()
if *filename != "" {
data, err := ioutil.ReadFile(*filename)
if err != nil {
fmt.Println(err.Error())
os.Exit(1)
}
file, err := parser.ParseFile(fset, *filename, data, 0)
if err != nil {
fmt.Println(err.Error())
os.Exit(1)
}
files := []*ast.File{file}
code, err := w.CompilePackage(fset, files, "main")
if err != nil {
if list, ok := err.(scanner.ErrorList); ok {
for _, e := range list {
fmt.Println(e.Error())
}
} else {
fmt.Println(err.Error())
}
os.Exit(1)
}
code, err = w.Compile(fset, "main()")
if err != nil {
fmt.Println(err.Error())
os.Exit(1)
}
_, err = code.Run()
if err != nil {
fmt.Println(err.Error())
os.Exit(1)
}
os.Exit(0)
}
fmt.Println(":: welcome to go-eval...")
fd := int(os.Stdin.Fd())
oldState, err := terminal.MakeRaw(fd)
if err != nil {
panic(err)
}
defer terminal.Restore(fd, oldState)
term := terminal.NewTerminal(&shell{r: os.Stdin, w: os.Stdout}, "> ")
if term == nil {
panic(errors.New("could not create terminal"))
}
//foo := 123
//w.DefineVar("foo", eval.TypeOfNative(foo), eval.ToValue(foo))
for {
line, err := term.ReadLine()
if err != nil {
break
}
code, err := w.Compile(fset, line)
if err != nil {
term.Write([]byte(err.Error() + "\n"))
continue
}
v, err := code.Run()
if err != nil {
term.Write([]byte(err.Error() + "\n"))
continue
}
if v != nil {
term.Write([]byte(v.String() + "\n"))
}
}
}