Option --dump¶ ↑

For other argument values, see Option –dump.

For the examples here, we use this program:

$ cat t.rb
puts 'Foo'

The supported dump items:

• insns: Instruction sequences:

  $ ruby --dump=insns t.rb
  == disasm: #<ISeq:<main>@t.rb:1 (1,0)-(1,10)> (catch: FALSE)
  0000 putself                                                          (   1)[Li]
  0001 putstring                              "Foo"
  0003 opt_send_without_block                 <calldata!mid:puts, argc:1, FCALL|ARGS_SIMPLE>
  0005 leave

• parsetree: Abstract syntax tree (AST):

  $ ruby --dump=parsetree t.rb
  ###########################################################
  ## Do NOT use this node dump for any purpose other than  ##
  ## debug and research.  Compatibility is not guaranteed. ##
  ###########################################################
  
  # @ NODE_SCOPE (line: 1, location: (1,0)-(1,10))
  # +- nd_tbl: (empty)
  # +- nd_args:
  # |   (null node)
  # +- nd_body:
  #     @ NODE_FCALL (line: 1, location: (1,0)-(1,10))*
  #     +- nd_mid: :puts
  #     +- nd_args:
  #         @ NODE_LIST (line: 1, location: (1,5)-(1,10))
  #         +- nd_alen: 1
  #         +- nd_head:
  #         |   @ NODE_STR (line: 1, location: (1,5)-(1,10))
  #         |   +- nd_lit: "Foo"
  #         +- nd_next:
  #             (null node)

• yydebug: Debugging information from yacc parser generator:

  $ ruby --dump=yydebug t.rb
  Starting parse
  Entering state 0
  Reducing stack by rule 1 (line 1295):
  lex_state: NONE -> BEG at line 1296
  vtable_alloc:12392: 0x0000558453df1a00
  vtable_alloc:12393: 0x0000558453df1a60
  cmdarg_stack(push): 0 at line 12406
  cond_stack(push): 0 at line 12407
  -> $$ = nterm $@1 (1.0-1.0: )
  Stack now 0
  Entering state 2
  Reading a token:
  lex_state: BEG -> CMDARG at line 9049
  Next token is token "local variable or method" (1.0-1.4: puts)
  Shifting token "local variable or method" (1.0-1.4: puts)
  Entering state 35
  Reading a token: Next token is token "string literal" (1.5-1.6: )
  Reducing stack by rule 742 (line 5567):
  $1 = token "local variable or method" (1.0-1.4: puts)
  -> $$ = nterm operation (1.0-1.4: )
  Stack now 0 2
  Entering state 126
  Reducing stack by rule 78 (line 1794):
  $1 = nterm operation (1.0-1.4: )
  -> $$ = nterm fcall (1.0-1.4: )
  Stack now 0 2
  Entering state 80
  Next token is token "string literal" (1.5-1.6: )
  Reducing stack by rule 292 (line 2723):
  cmdarg_stack(push): 1 at line 2737
  -> $$ = nterm $@16 (1.4-1.4: )
  Stack now 0 2 80
  Entering state 235
  Next token is token "string literal" (1.5-1.6: )
  Shifting token "string literal" (1.5-1.6: )
  Entering state 216
  Reducing stack by rule 607 (line 4706):
  -> $$ = nterm string_contents (1.6-1.6: )
  Stack now 0 2 80 235 216
  Entering state 437
  Reading a token: Next token is token "literal content" (1.6-1.9: "Foo")
  Shifting token "literal content" (1.6-1.9: "Foo")
  Entering state 503
  Reducing stack by rule 613 (line 4802):
  $1 = token "literal content" (1.6-1.9: "Foo")
  -> $$ = nterm string_content (1.6-1.9: )
  Stack now 0 2 80 235 216 437
  Entering state 507
  Reducing stack by rule 608 (line 4716):
  $1 = nterm string_contents (1.6-1.6: )
  $2 = nterm string_content (1.6-1.9: )
  -> $$ = nterm string_contents (1.6-1.9: )
  Stack now 0 2 80 235 216
  Entering state 437
  Reading a token:
  lex_state: CMDARG -> END at line 7276
  Next token is token "terminator" (1.9-1.10: )
  Shifting token "terminator" (1.9-1.10: )
  Entering state 508
  Reducing stack by rule 590 (line 4569):
  $1 = token "string literal" (1.5-1.6: )
  $2 = nterm string_contents (1.6-1.9: )
  $3 = token "terminator" (1.9-1.10: )
  -> $$ = nterm string1 (1.5-1.10: )
  Stack now 0 2 80 235
  Entering state 109
  Reducing stack by rule 588 (line 4559):
  $1 = nterm string1 (1.5-1.10: )
  -> $$ = nterm string (1.5-1.10: )
  Stack now 0 2 80 235
  Entering state 108
  Reading a token:
  lex_state: END -> BEG at line 9200
  Next token is token '\n' (1.10-1.10: )
  Reducing stack by rule 586 (line 4541):
  $1 = nterm string (1.5-1.10: )
  -> $$ = nterm strings (1.5-1.10: )
  Stack now 0 2 80 235
  Entering state 107
  Reducing stack by rule 307 (line 2837):
  $1 = nterm strings (1.5-1.10: )
  -> $$ = nterm primary (1.5-1.10: )
  Stack now 0 2 80 235
  Entering state 90
  Next token is token '\n' (1.10-1.10: )
  Reducing stack by rule 261 (line 2553):
  $1 = nterm primary (1.5-1.10: )
  -> $$ = nterm arg (1.5-1.10: )
  Stack now 0 2 80 235
  Entering state 220
  Next token is token '\n' (1.10-1.10: )
  Reducing stack by rule 270 (line 2586):
  $1 = nterm arg (1.5-1.10: )
  -> $$ = nterm arg_value (1.5-1.10: )
  Stack now 0 2 80 235
  Entering state 221
  Next token is token '\n' (1.10-1.10: )
  Reducing stack by rule 297 (line 2779):
  $1 = nterm arg_value (1.5-1.10: )
  -> $$ = nterm args (1.5-1.10: )
  Stack now 0 2 80 235
  Entering state 224
  Next token is token '\n' (1.10-1.10: )
  Reducing stack by rule 772 (line 5626):
  -> $$ = nterm none (1.10-1.10: )
  Stack now 0 2 80 235 224
  Entering state 442
  Reducing stack by rule 296 (line 2773):
  $1 = nterm none (1.10-1.10: )
  
  -> $$ = nterm opt_block_arg (1.10-1.10: )
  Stack now 0 2 80 235 224
  Entering state 441
  Reducing stack by rule 288 (line 2696):
  $1 = nterm args (1.5-1.10: )
  $2 = nterm opt_block_arg (1.10-1.10: )
  -> $$ = nterm call_args (1.5-1.10: )
  Stack now 0 2 80 235
  Entering state 453
  Reducing stack by rule 293 (line 2723):
  $1 = nterm $@16 (1.4-1.4: )
  $2 = nterm call_args (1.5-1.10: )
  cmdarg_stack(pop): 0 at line 2754
  -> $$ = nterm command_args (1.4-1.10: )
  Stack now 0 2 80
  Entering state 333
  Next token is token '\n' (1.10-1.10: )
  Reducing stack by rule 79 (line 1804):
  $1 = nterm fcall (1.0-1.4: )
  $2 = nterm command_args (1.4-1.10: )
  -> $$ = nterm command (1.0-1.10: )
  Stack now 0 2
  Entering state 81
  Next token is token '\n' (1.10-1.10: )
  Reducing stack by rule 73 (line 1770):
  $1 = nterm command (1.0-1.10: )
  -> $$ = nterm command_call (1.0-1.10: )
  Stack now 0 2
  Entering state 78
  Reducing stack by rule 51 (line 1659):
  $1 = nterm command_call (1.0-1.10: )
  -> $$ = nterm expr (1.0-1.10: )
  Stack now 0 2
  Entering state 75
  Next token is token '\n' (1.10-1.10: )
  Reducing stack by rule 39 (line 1578):
  $1 = nterm expr (1.0-1.10: )
  -> $$ = nterm stmt (1.0-1.10: )
  Stack now 0 2
  Entering state 73
  Next token is token '\n' (1.10-1.10: )
  Reducing stack by rule 8 (line 1354):
  $1 = nterm stmt (1.0-1.10: )
  -> $$ = nterm top_stmt (1.0-1.10: )
  Stack now 0 2
  Entering state 72
  Reducing stack by rule 5 (line 1334):
  $1 = nterm top_stmt (1.0-1.10: )
  -> $$ = nterm top_stmts (1.0-1.10: )
  Stack now 0 2
  Entering state 71
  Next token is token '\n' (1.10-1.10: )
  Shifting token '\n' (1.10-1.10: )
  Entering state 311
  Reducing stack by rule 769 (line 5618):
  $1 = token '\n' (1.10-1.10: )
  -> $$ = nterm term (1.10-1.10: )
  Stack now 0 2 71
  Entering state 313
  Reducing stack by rule 770 (line 5621):
  $1 = nterm term (1.10-1.10: )
  -> $$ = nterm terms (1.10-1.10: )
  Stack now 0 2 71
  Entering state 314
  Reading a token: Now at end of input.
  Reducing stack by rule 759 (line 5596):
  $1 = nterm terms (1.10-1.10: )
  -> $$ = nterm opt_terms (1.10-1.10: )
  Stack now 0 2 71
  Entering state 312
  Reducing stack by rule 3 (line 1321):
  $1 = nterm top_stmts (1.0-1.10: )
  $2 = nterm opt_terms (1.10-1.10: )
  -> $$ = nterm top_compstmt (1.0-1.10: )
  Stack now 0 2
  Entering state 70
  Reducing stack by rule 2 (line 1295):
  $1 = nterm $@1 (1.0-1.0: )
  $2 = nterm top_compstmt (1.0-1.10: )
  vtable_free:12426: p->lvtbl->args(0x0000558453df1a00)
  vtable_free:12427: p->lvtbl->vars(0x0000558453df1a60)
  cmdarg_stack(pop): 0 at line 12428
  cond_stack(pop): 0 at line 12429
  -> $$ = nterm program (1.0-1.10: )
  Stack now 0
  Entering state 1
  Now at end of input.
  Shifting token "end-of-input" (1.10-1.10: )
  Entering state 3
  Stack now 0 1 3
  Cleanup: popping token "end-of-input" (1.10-1.10: )
  Cleanup: popping nterm program (1.0-1.10: )

Additional flags can follow dump items.

• +comment: Add comments to AST.

• +error-tolerant: Parse in error-tolerant mode.

• -optimize: Disable optimizations for instruction sequences.