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Question 27528: Empty Language, Epsilon, Wildcards and Bounded Equality Are Not Interchangeable

On this page
  1. Original question and givens
  2. Definition and scope
  3. Step-by-step derivation
  4. Reverse checks
  5. Result
  6. This question review and source binding

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R0054-27528 · q-20261015-advance-20261118-r06-regular-expression-0078

Original question and givens

Use mode=wildcard_confusion, complete model={"alphabet":["a","b"],"token":"?"}. Give (mode, alphabet, wildcard_token, core_AST_node_qualification, boundary).

  • G001 — Use mode=wildcard_confusion, complete model={"alphabet":["a","b"],"token":"?"}. Give (mode, alphabet, wildcard_token, core_AST_node_qualification, boundary).

Definition and scope

Use the original question domain, assumptions and cited MKO definitions. This item has second-context mathematical and bilingual review, with the model, answer and every arithmetic step independently recomputed from the original parameters; the source question remains a candidate.

Step-by-step derivation

S001 · implies

Before

source roles = [regex-boundary]

After

derived = [[mode, alphabet, wildcard_token, core_AST_node_qualification, boundary]]

Conditions: none

List the complete operation/mode field order without JavaScript or answer-shape inference;Boolean,string,null and an unclaimed result remain distinct.

Step identifiers and dependencies

Rule: source_ordered_fields_without_JS · Uses: G001

S002 · implies

Before

source roles = [[a, b], ?]

After

derived = [No]

Conditions: none

A shell wildcard token is not this core typed AST node.AST star is the explicit Kleene operation with a child,not an arbitrary string token.A separately declared literal alphabet symbol is a different matter.

Step identifiers and dependencies

Rule: Regex_shell_token_NOT_core_typed_AST_operator · Uses: G001, S001

Reverse checks

  • S002 · premise_and_result_audit — Reverse-check original data,operands,complete scope and premises;finite witnesses,conditional theorem use and formal proof remain distinct.
  • S001 · premise_and_result_audit — Reverse-check original data,operands,complete scope and premises;finite witnesses,conditional theorem use and formal proof remain distinct.

Result

(wildcard_confusion, [a, b], ?, No, shell_wildcard_is_not_a_core_regex_AST_node)

The full substitutions and premise checks give the original answer; source identity,format and status are unchanged.

This question review and source binding

Review date: 2026-10-26

Original questions, answers, step expressions, numeric ASTs and historical records are retained. Source candidate labels remain historical and are not overwritten as formal proof.

Source hashes and review receipts
  • input commit: 0f7be61e2c22317a4075561dc822c87d881a50db
  • original question SHA-256: 040c449a99482b9cc9599776b435f9a4dc97cfa4339d6ae9b523e5ffa1f701d3
  • candidate record SHA-256: f3e7e3ba8ccdc5408f6d18af5435404cdee6cfb7324de61b4375cb384ce9b9e0
  • semantic review receipt SHA-256: 0a76d8e93c08bb16998a0483f3dfc0504f269fc3e1982e6cd868cab0a2856d54
  • question-first witness SHA-256: 09127b736c225714dfa0b7ceb0e6a6e66df27438b480cad8217d3c2f99ce9437
  • Lean: NOT_RUN · human review: NOT_PERFORMED
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