6.7 Keigakomi (罫囲み)

Synopsis

Keigakomi draws a ruled frame (a box) around a block of text — used for notices, inset boxes, and the like.

Notation

A paired block container:

［＃罫囲み］
枠の中の文章。
［＃罫囲み終わり］

keigakomi-open  = LBRACK HASH %s"罫囲み" RBRACK
keigakomi-close = LBRACK HASH %s"罫囲み終わり" RBRACK

The official guide also writes this block as ［＃ここから罫囲み］ … ［＃ここで罫囲み終わり］. The bare opener/closer above is the canonical pair in this specification; the ここから/ここで variant is an accepted equivalent and pairs by the same keigakomi family.

There is also an inline forward-reference form that boxes a single run, the span-level counterpart of the block container (parallel to how 太字 has both a block range and a は-form leaf, §6.12):

注意［＃「注意」は罫囲み］事項。
新興河上［＃「新興河上」に枠囲み］      ← に particle + 枠囲み spelling

keigakomi-inline = target "［＃「" target "」" (%s"は" / %s"に") %s"罫囲み" "］"

Unlike 太字/斜体 (は-only, §6.12), the frame decoration accepts either particle — は ("is framed") or に ("frame applied to"). The core recognises only the canonical keyword 罫囲み. The corpus-rare, non-canonical spellings 枠囲み / 枠囲い (and the rule-style names 表罫囲み / ミシン罫囲み) are not folded onto 罫囲み — that would erase their spelling; they degrade to a lossless Unknown directive (§6.14) with a lint suggesting は罫囲み (#435).

Box-character enclosure (「□」囲み)

A second inline form names the enclosing glyph explicitly, in a quoted token after the particle:

一［＃「一」は「□」囲み］

box-enclosure = target "［＃「" target "」" %s"は「" box-glyph %s"」囲み" "］"
box-glyph     = %x25A1   ; □ (U+25A1) — the only attested glyph

This is the same enclosure family as 罫囲み — it boxes the target run — but a distinct style: a box glyph rather than a ruled frame. The □ names an enclosure kind, not free data; a future non-□ glyph would be a further named kind (compare 二重罫囲み / 点線丸囲み), never an arbitrary character. The look-back rule of §7.5 consumes the preceding literal exactly as the other は-form leaves.

Parameters

None for the block form. The inline form names a single target (the quoted run to box), resolved by the look-back rule of §7.5.

Semantics

• The opener/closer pair (§7.1) yields a container node (family keigakomi) governing the enclosed block; it nests with other block containers (§7.3).
• The inline forward-reference form yields an emphasis node over its target run and is an inline construct. The box-character form (「X」は「□」囲み) likewise yields an emphasis node over its target.
• Reference rendering (§8) is <div class="aozora-container aozora-container-keigakomi">…</div> for the block form, <span class="aozora-keigakomi-inline">…</span> for the inline rule form, and <span class="aozora-keigakomi-box">…</span> for the box-character form (the box is drawn by the stylesheet, so the □ glyph is not emitted into the body).
• Serialization reconstructs the block opener/closer byte-exact (§7.6); the canonical inline rule form (は罫囲み / に罫囲み) reconstructs its particle and keyword byte-exact, and the box form reconstructs 「X」は「□」囲み byte-exact — all idempotent. The non-canonical 枠囲み / 枠囲い are not recognised (they degrade, §6.14, and round-trip verbatim as an Unknown).

Error conditions

• mismatched-container-close — closed by a different container family.
• unclosed-bracket — opener with no closer.

Conformance vectors

keigakomi_container, keigakomi_inline_forward, keigakomi_inline_framed, box_enclosure, box_enclosure_no_referent.