[mmastrac]

This paper is fascinating. I have an extremely fast JSON parser for Java that I've been working on, on and off [1], and I'd love to optionally augment it with semi-indexes for cases where end-users are using a subset of a file.

[1] https://github.com/mmastrac/nanojson

[ot]

Very interesting! Implementing a semi-index is very easy if you have implementations of Elias-Fano and balanced parentheses data structures.

For Java I recommend Sux4j [1] that has a very good implementation of Elias-Fano, but I think that balanced parentheses are very primitive. I was told by the author that a better data structure, based on Range-Min-Max trees, should be added soon.

[1] http://sux.dsi.unimi.it/