// Eval evaluates the input string and returns its output.
// If execution caused errors, they will be returned concatenated
// together in the error value returned.
// TODO: Should it stop at first error?
func Eval(expr string) (result string, errors error) {
if !strings.HasSuffix(expr, "\n") {
expr += "\n"
}
reader := strings.NewReader(expr)
stdout := new(bytes.Buffer)
stderr := new(bytes.Buffer)
conf.SetOutput(stdout)
conf.SetErrOutput(stderr)
scanner := scan.New(&conf, context, " ", reader)
parser := parse.NewParser(&conf, " ", scanner, context)
for !run.Run(parser, context, false) {
}
var err error
if stderr.Len() > 0 {
err = fmt.Errorf("%s", stderr)
}
return stdout.String(), err
}
func main() {
flag.Usage = usage
flag.Parse()
if *origin != 0 && *origin != 1 {
fmt.Fprintf(os.Stderr, "ivy: illegal origin value %d\n", *origin)
os.Exit(2)
}
if *gformat {
*format = "%.12g"
}
conf.SetFormat(*format)
conf.SetMaxBits(*maxbits)
conf.SetMaxDigits(*maxdigits)
conf.SetOrigin(*origin)
conf.SetPrompt(*prompt)
if len(*debugFlag) > 0 {
for _, debug := range strings.Split(*debugFlag, ",") {
if !conf.SetDebug(debug, true) {
fmt.Fprintf(os.Stderr, "ivy: unknown debug flag %q", debug)
os.Exit(2)
}
}
}
value.SetConfig(&conf)
context = exec.NewContext()
value.SetContext(context)
run.SetConfig(&conf)
if *execute {
runArgs(context)
return
}
if flag.NArg() > 0 {
for i := 0; i < flag.NArg(); i++ {
name := flag.Arg(i)
var fd io.Reader
var err error
interactive := false
if name == "-" {
interactive = true
fd = os.Stdin
} else {
interactive = false
fd, err = os.Open(name)
}
if err != nil {
fmt.Fprintf(os.Stderr, "ivy: %s\n", err)
os.Exit(1)
}
scanner := scan.New(&conf, context, name, bufio.NewReader(fd))
parser := parse.NewParser(&conf, name, scanner, context)
if !run.Run(parser, context, interactive) {
break
}
}
return
}
scanner := scan.New(&conf, context, "<stdin>", bufio.NewReader(os.Stdin))
parser := parse.NewParser(&conf, "<stdin>", scanner, context)
for !run.Run(parser, context, true) {
}
}
// runArgs executes the text of the command-line arguments as an ivy program.
func runArgs(context value.Context) {
scanner := scan.New(&conf, context, "<args>", strings.NewReader(strings.Join(flag.Args(), " ")))
parser := parse.NewParser(&conf, "<args>", scanner, context)
run.Run(parser, context, false)
}