func (e *Evaluator) funcCall(v *ast.FuncCallExpr) bool {
f, ok := Funcs[v.FnName.L]
if !ok {
e.err = ErrInvalidOperation.Gen("unknown function %s", v.FnName.O)
return false
}
if len(v.Args) < f.MinArgs || (f.MaxArgs != -1 && len(v.Args) > f.MaxArgs) {
e.err = ErrInvalidOperation.Gen("number of function arguments must in [%d, %d].", f.MinArgs, f.MaxArgs)
return false
}
a := make([]types.Datum, len(v.Args))
for i, arg := range v.Args {
a[i] = *arg.GetDatum()
}
val, err := f.F(a, e.ctx)
if err != nil {
e.err = errors.Trace(err)
return false
}
v.SetDatum(val)
return true
}
