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Module `Parsexp_symbolic_automaton`

Abstract version of the parsing automaton.

It is used in two places:

to define the automaton and generate parser code.
for tests

At parser runtime, we instead use an integer for states and a table of functions for transitions

It is possible that a modern and good parser generator can simplify the parser definition further.

We didn't use an existing parser generator like ocamlyacc or menhir because we wanted to have a very precise control over performance and a good API for incremental parsing.

At the time Parsexp was written, sexp parsers written using parser generators ran more slowly, allocated more, and were difficult to integrate with monadic IOs.

Sexplib had both a lex/yacc generated parser and a handwritten one for performance. Parsexp had to match the performance of the handwritten parser (which we did, with less allocation).

module Automaton : sig ... end

module Parse_error_reason : sig ... end

module Table : sig ... end

val table : Table.t