Properly emoji-gate 'async' on resource.drop in Explainer.md

Author: lukewagner

design/mvp/Binary.md

@@ -214,7 +214,7 @@ label'        ::= len:<u32> l:<label>                     => l    (if len = |l|)
 valtype       ::= i:<typeidx>                             => i
                 | pvt:<primvaltype>                       => pvt
 resourcetype  ::= 0x3f 0x7f f?:<funcidx>?                 => (resource (rep i32) (dtor f)?)
-                | 0x3e 0x7f f:<funcidx> cb?:<funcidx>?    => (resource (rep i32) (dtor async f (callback cb)?))
+                | 0x3e 0x7f f:<funcidx> cb?:<funcidx>?    => (resource (rep i32) (dtor async f (callback cb)?)) 🚝
 functype      ::= 0x40 ps:<paramlist> rs:<resultlist>     => (func ps rs)
 paramlist     ::= lt*:vec(<labelvaltype>)                 => (param lt)*
 resultlist    ::= 0x00 t:<valtype>                        => (result t)
@@ -288,7 +288,7 @@ canon    ::= 0x00 0x00 f:<core:funcidx> opts:<opts> ft:<typeidx> => (canon lift
            | 0x01 0x00 f:<funcidx> opts:<opts>                   => (canon lower f opts (core func))
            | 0x02 rt:<typeidx>                                   => (canon resource.new rt (core func))
            | 0x03 rt:<typeidx>                                   => (canon resource.drop rt (core func))
-           | 0x07 rt:<typeidx>                                   => (canon resource.drop rt async (core func)) 🔀
+           | 0x07 rt:<typeidx>                                   => (canon resource.drop rt async (core func)) 🚝
            | 0x04 rt:<typeidx>                                   => (canon resource.rep rt (core func))
            | 0x08                                                => (canon backpressure.set (core func)) 🔀
            | 0x09 rs:<resultlist> opts:<opts>                    => (canon task.return rs opts (core func)) 🔀

design/mvp/Explainer.md

@@ -566,7 +566,8 @@ defvaltype    ::= bool
                 | (future <typeidx>?) 🔀
 valtype       ::= <typeidx>
                 | <defvaltype>
-resourcetype  ::= (resource (rep i32) (dtor async? <funcidx> (callback <funcidx>)?)?)
+resourcetype  ::= (resource (rep i32) (dtor <funcidx>)?)
+                | (resource (rep i32) (dtor async <funcidx> (callback <funcidx>)?)?) 🚝
 functype      ::= (func (param "<label>" <valtype>)* (result <valtype>)?)
 componenttype ::= (component <componentdecl>*)
 instancetype  ::= (instance <instancedecl>*)
@@ -1411,7 +1412,8 @@ dynamically interact with Canonical ABI entities like resources,
 ```ebnf
 canon ::= ...
         | (canon resource.new <typeidx> (core func <id>?))
-        | (canon resource.drop <typeidx> async? (core func <id>?))
+        | (canon resource.drop <typeidx> (core func <id>?))
+        | (canon resource.drop <typeidx> async (core func <id>?)) 🚝
         | (canon resource.rep <typeidx> (core func <id>?))
         | (canon context.get <valtype> <u32> (core func <id>?)) 🔀
         | (canon context.set <valtype> <u32> (core func <id>?)) 🔀
@@ -1478,7 +1480,7 @@ When the `async` immediate is false:
 | Approximate WIT signature  | `func<T>(t: T)`                    |
 | Canonical ABI signature    | `[t:i32] -> []`                    |
 
-When the `async` immediate is true:
+🚝 When the `async` immediate is true:
 
 | Synopsis                   |                                    |
 | -------------------------- | ---------------------------------- |