Can lyrics be added interleaved with notation in lilypond

Question

When writing vocal music in lilypond, I find it easier to find my place when there are lyrics in near proximity to the notes, so I've been using linebreaks and comments to achieve this so far:

\relative c' {
  c4 d e f | g a b c | % lyrics to the notes go here for myself
  c4 b a g | f e d c | % more words ...
  % ... and so on
}

The problem is that I then have to duplicate all the lyrics when I go to add lyrics. What I would like, is to interleave my lyrics with the music as I go. Something like this:

\score {
\new PianoStaff
\new Staff = "upper" \relative c' {
  \clef treble
  \key c \major
  \time 4/4
  { c d e f | g a b c } \addlyrics { do re mi fa so la ti do } % seems to stop rendering after this point
  { c b a g | f e d c } \addlyrics { do ti la so fa mi re do } 
}
\layout { }
}

But after the the first \addlyrics, no more music is rendered for the staff. Does anyone know how I can make this technique work?

Answer 1

A quick and dirty way of doing this is to put your music and lyrics into variables like this:

musicA={c d e f | g a b c}
lyricsA=\lyricmode {do re mi fa so la ti do}
musicB={c b a g | f e d c}
lyricsB=\lyricmode {do ti la so fa mi re do}
<<
\new Voice = "melody" \relative c' {
\musicA
\musicB
}
\new Lyrics \lyricsto "melody" {
\lyricsA
\lyricsB
}
>>

This approach might get quite unwieldy for a longer song, though.

Answer 2

Found something useful in the documentation called \parallelMusic which lets me write my score like this:

\parallelMusic #'(music words) {
  c d e f g a b c | \lyricmode { do re mi fa so la ti do } |
  c b a g f e d c | \lyricmode { do ti la so fa mi re do } |
}

\score {
\new PianoStaff
\new Staff = "upper" \relative c' {
  \clef treble
  \key c \major
  \time 4/4
  \music \addlyrics \words
}
\layout { }
}

This is similar to @Bob's answer in that it assigns the separate pieces to variables and joins them later, but the \parallelMusic command makes it look pretty snazzy. I do lose the ability to have internal bar checks if I want more than one bar on a line, but I can live with that.