func use(ec *EvalCtx, modname string, pfilename *string) {
if _, ok := ec.Evaler.Modules[modname]; ok {
// Module already loaded.
return
}
// Load the source.
var filename, source string
if pfilename != nil {
filename = *pfilename
var err error
source, err = readFileUTF8(filename)
maybeThrow(err)
} else {
// No filename; defaulting to $datadir/$modname.elv.
dataDir, err := store.DataDir()
maybeThrow(err)
filename = dataDir + "/" + modname + ".elv"
if _, err := os.Stat(filename); os.IsNotExist(err) {
// File does not exist. Try loading from the table of builtin
// modules.
var ok bool
if source, ok = builtinModules[modname]; ok {
// Source is loaded. Do nothing more.
filename = "<builtin module>"
} else {
throw(fmt.Errorf("cannot load %s: %s does not exist", modname, filename))
}
} else {
// File exists. Load it.
source, err = readFileUTF8(filename)
maybeThrow(err)
}
}
// TODO(xiaq): Should handle failures when evaluting the module
newEc := &EvalCtx{
ec.Evaler,
filename, source, "module " + modname,
Namespace{}, Namespace{},
ec.ports, nil,
0, len(source),
}
n, err := parse.Parse(source)
maybeThrow(err)
op, err := newEc.Compile(n)
// TODO the err originates in another source, should add appropriate information.
maybeThrow(err)
op.Exec(newEc)
ec.Evaler.Modules[modname] = newEc.local
}
func use(ec *EvalCtx, modname string, pfilename *string) {
if _, ok := ec.Evaler.Modules[modname]; ok {
// Module already loaded.
return
}
// Load the source.
var filename, source string
if pfilename != nil {
filename = *pfilename
var err error
source, err = readFileUTF8(filename)
maybeThrow(err)
} else {
// No filename; defaulting to $datadir/$modname.elv.
dataDir, err := store.DataDir()
maybeThrow(err)
filename = dataDir + "/" + strings.Replace(modname, ":", "/", -1) + ".elv"
if _, err := os.Stat(filename); os.IsNotExist(err) {
// File does not exist. Try loading from the table of builtin
// modules.
var ok bool
if source, ok = builtinModules[modname]; ok {
// Source is loaded. Do nothing more.
filename = "<builtin module>"
} else {
throw(fmt.Errorf("cannot load %s: %s does not exist", modname, filename))
}
} else {
// File exists. Load it.
source, err = readFileUTF8(filename)
maybeThrow(err)
}
}
n, err := parse.Parse(filename, source)
maybeThrow(err)
// Make an empty namespace.
local := Namespace{}
// TODO(xiaq): Should handle failures when evaluting the module
newEc := &EvalCtx{
ec.Evaler, "module " + modname,
filename, source,
local, Namespace{},
ec.ports, nil, true,
0, len(source), ec.addTraceback(), false,
}
op, err := newEc.Compile(n, filename, source)
// TODO the err originates in another source, should add appropriate information.
maybeThrow(err)
// Load the namespace before executing. This avoids mutual and self use's to
// result in an infinite recursion.
ec.Evaler.Modules[modname] = local
err = newEc.PEval(op)
if err != nil {
// Unload the namespace.
delete(ec.Modules, modname)
throw(err)
}
}