Full Idea
Compositionality is best seen as saying the semantic value of a string is explained by the strings lower down its parsing tree. It is unimportant whether a string is always parsed in terms of its own substrings.
Clarification
The 'parsing tree' is tha analysis of meaning into branching components
Gist of Idea
Compositionality should rely on the parsing tree, which may contain more than sentence components
Source
Michael Potter (The Rise of Analytic Philosophy 1879-1930 [2020], 05 'Sem')
Book Reference
Potter,Michael: 'The Rise of Anaytic Philosophy 1879-1930' [Routledge 2020], p.41
A Reaction
That is, the analysis must explain the meaning, but the analysis can contain more than the actual ingredients of the sentence (which would be too strict).
Related Idea
Idea 22282 'Direct compositonality' says the components wholly explain a sentence meaning [Potter]