/
concat.go
57 lines (55 loc) · 940 Bytes
/
concat.go
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package sb
func ConcatSinks(sinks ...Sink) Sink {
if len(sinks) == 0 {
return nil
}
for sinks[0] == nil {
sinks = sinks[1:]
if len(sinks) == 0 {
return nil
}
}
var sink Sink
sink = func(token *Token) (Sink, error) {
var err error
sinks[0], err = sinks[0].Sink(token)
if err != nil {
return nil, err
}
for sinks[0] == nil {
sinks = sinks[1:]
if len(sinks) == 0 {
return nil, nil
}
}
return sink, nil
}
return sink
}
func ConcatStreams(streams ...Stream) Stream {
if len(streams) == 0 {
return nil
}
for streams[0] == nil {
streams = streams[1:]
if len(streams) == 0 {
return nil
}
}
var proc Proc
proc = func(token *Token) (Proc, error) {
err := streams[0].Next(token)
if err != nil {
return nil, err
}
if token.Invalid() {
streams = streams[1:]
if len(streams) == 0 {
return nil, nil
}
return proc, nil
}
return proc, nil
}
return &proc
}