diff --git a/attribute types.txt b/attribute types.txt
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+(meter) min, max, low, high, optimum, value: R
+(progress) max, value: R
+DONE WITH FLOATS.
+
+width, height: N
+maxlength, minlength: N
+rows: N⁺
+rowspan: {x in N | x ≤ 65534}
+cols: N⁺
+colspan: {x in N⁺ | x ≤ 1000}
+size: N⁺
+tabindex: Z
+DONE WITH INTEGERS.
+
+step: R⁺ U {"any"}
+  - This will be a one-off. I can either feed it a *float32 and count the null as
+  many, or I can define a new `type StepValue *float32` with a couple of helper
+  functions `StepAny() StepValue {return nil}`
+  and `StepInt(value int) StepValue {return StepValue(&value)}`.
+DONE WITH STEP.
+
+EXPLICIT BOOLS:
+contenteditable: explicit bool
+draggable: explicit bool
+spellcheck: explicit bool
+DONE WITH EXPLICIT BOOLS.
+
+accesskey: either a single printable character, or (poorly supported) a space-delimited list of characters
+DONE WITH ACCESSKEY.
+
+STRINGS:
+action: URL (string)
+alt: string
+charset: IANA MIME encoding name (string)
+cite: URI (string)
+content: string
+contextmenu: menu ID (string)
+data: URL (string)
+dirname: the the element's name ++ ".dir", or maybe any string; needs more research
+download: destination filename (string)
+form: ID of form (string)
+formaction: URL (string)
+href: URL (string)
+hreflang: a string from the grammar specified in https://www.ietf.org/rfc/bcp/bcp47.txt
+id: string
+itemprop: string
+label: string
+lang: language tag specified in https://www.ietf.org/rfc/bcp/bcp47.txt (string)
+list: ID of datalist (string)
+media: CSS media query (string)
+name: string
+pattern: regex (string)
+placeholder: string
+poster: URL (string)
+src: URL (string)
+srcdoc: inline HTML (string)
+srclang: language tag specified in https://www.ietf.org/rfc/bcp/bcp47.txt (string)
+style: CSS (string)
+title: string
+usemap: URL fragment including "#" (string)
+
+COMMA LISTS:
+accept: comma-delimited list of MIME types, "audio/*", "video/*", "image/*", or file extension starting with "."
+srcset: comma-delimited list of image descriptors; see https://developer.mozilla.org/en-US/docs/Web/HTML/Element/source#attr-srcset
+coords: comma-delimited list of floats; count depends on shape attribute value
+  rect → two x,y pairs: left, top, right, bottom
+  circle → x,y,r
+  poly → at least three x,y pairs
+
+SPACE LISTS:
+accept-charset: space- or comma-delimited list of character encodings
+class: space-delimited list of string
+for: space-delimited list of IDs
+headers: space-delimited list of IDs
+ping: space-delimited list of URLs
+rel: space-delimited list of large enum
+sandbox: space-delimited list of large enum
+DONE WITH SPACE LISTS.
+
+autocapitalize: enum {none, sentences, words, characters}
+crossorigin: enum {anonymous, use-credentials}
+decoding: enum {sync, async, auto}
+dir: enum {ltr, rtl, auto}
+enctype: enum {application/x-www-form-urlencoded, multipart/form-data, text/plain}
+http-equiv: enum {content-security-policy, refresh}
+kind: enum {subtitles, captions, descriptions, chapters, metadata}
+method: enum {post, get, dialog}
+preload: enum {none, metadata, auto}
+referrerpolicy: enum {no-referrer, no-referrer-when-downgrade, origin, origin-when-cross-origin, same-origin, strict-origin, strict-origin-when-cross-origin, unsafe-url}
+scope: enum {row, col, rowgroup, colgroup, auto}
+shape: enum {rect, circle, poly, default}
+target: enum {_self, _blank, _parent, _top}; also iframe name for <form>
+wrap: enum {hard, soft}
+
+autocomplete:
+  form → enum {on, off}
+  input → enum (many options)
+  textarea → same as for input
+datetime: an unholy union of fifty million date, time, and offset formats (string)
+  ins → date with optional time
+  del → date with optional time
+  datetime → an unholy union of fifty million date, time, and offset formats, representing a date or time in one place or everywhere (string)
+sizes: three different definitions for <link>, <img>, and <source> >:(
+type:
+  button → enum {submit, reset, button}
+  input → large enum
+  embed → MIME type (string)
+  object → content type (string)
+  script → "text/javascript", "module", or any other MIME type
+  source → MIME type with an optional codecs parameter as in https://tools.ietf.org/html/rfc4281
+  style → MIME type
+value:
+  button → string
+  data → string
+  input → string
+  li → int
+  meter → float
+  option → string
+  progress → float
+  param → string