// Parse and evaluate a given script for the scope.
// Returns a set of default vars.
// If a set of predefined vars is provided, they may effect the default var values.
func Evaluate(script string, scope *stateful.Scope, predefinedVars map[string]Var, ignoreMissingVars bool) (_ map[string]Var, err error) {
defer func(errP *error) {
r := recover()
if r == ErrEmptyStack {
trace := make([]byte, 1024)
n := runtime.Stack(trace, false)
*errP = fmt.Errorf("evaluation caused stack error: %v Go Trace: %s", r, string(trace[:n]))
} else if r != nil {
panic(r)
}
}(&err)
root, err := ast.Parse(script)
if err != nil {
return nil, err
}
// Use a stack machine to evaluate the AST
stck := &stack{}
// Collect any defined defaultVars
defaultVars := make(map[string]Var)
err = eval(root, scope, stck, predefinedVars, defaultVars, ignoreMissingVars)
if err != nil {
return nil, err
}
return defaultVars, nil
}
// Formats a TICKscript according to the standard.
func Format(script string) (string, error) {
root, err := ast.Parse(script)
if err != nil {
return "", err
}
var buf bytes.Buffer
buf.Grow(len(script))
root.Format(&buf, "", false)
return buf.String(), nil
}