1Parsing(3)                       OCaml library                      Parsing(3)
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NAME

6       Parsing - The run-time library for parsers generated by ocamlyacc.
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Module

9       Module   Parsing
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Documentation

12       Module Parsing
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16       The run-time library for parsers generated by ocamlyacc .
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23       val symbol_start : unit -> int
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26       symbol_start and Parsing.symbol_end are to be called in the action part
27       of a grammar rule only. They return  the  offset  of  the  string  that
28       matches the left-hand side of the rule: symbol_start() returns the off‐
29       set of the first character; symbol_end() returns the offset  after  the
30       last character. The first character in a file is at offset 0.
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34       val symbol_end : unit -> int
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36       See Parsing.symbol_start .
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40       val rhs_start : int -> int
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42       Same  as  Parsing.symbol_start  and Parsing.symbol_end , but return the
43       offset of the string matching the n th item on the right-hand  side  of
44       the  rule,  where n is the integer parameter to rhs_start and rhs_end .
45       n is 1 for the leftmost item.
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49       val rhs_end : int -> int
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51       See Parsing.rhs_start .
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55       val symbol_start_pos : unit -> Lexing.position
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57       Same as symbol_start , but return a position instead of an offset.
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61       val symbol_end_pos : unit -> Lexing.position
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63       Same as symbol_end , but return a position instead of an offset.
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67       val rhs_start_pos : int -> Lexing.position
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69       Same as rhs_start , but return a position instead of an offset.
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73       val rhs_end_pos : int -> Lexing.position
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75       Same as rhs_end , but return a position instead of an offset.
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79       val clear_parser : unit -> unit
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81       Empty the parser stack. Call it  just  after  a  parsing  function  has
82       returned,  to  remove  all pointers from the parser stack to structures
83       that were built by semantic actions during parsing.  This is  optional,
84       but lowers the memory requirements of the programs.
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88       exception Parse_error
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91       Raised  when  a  parser  encounters a syntax error.  Can also be raised
92       from the action part of a grammar rule, to initiate error recovery.
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96       val set_trace : bool -> bool
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98       Control debugging support  for  ocamlyacc  -generated  parsers.   After
99       Parsing.set_trace  true  ,  the  pushdown  automaton  that executes the
100       parsers prints a trace of its actions  (reading  a  token,  shifting  a
101       state, reducing by a rule) on standard output.  Parsing.set_trace false
102       turns this debugging trace off.  The boolean returned is  the  previous
103       state of the trace flag.
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106       Since 3.11.0
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112OCamldoc                          2020-02-27                        Parsing(3)