The current spec gives this abbreviation for specifying data inline in a memory definition:

'(' 'memory' id? '(' 'data' b*:datastring ')' ')'

The memory limits are inferred from the size of the data string. For back compat, this abbreviation needs to continue specifying a 32-bit memory, but should we add a similar abbreviation for 64-bit memories? As an example:

'(' 'memory' id? '(' 'data' 'i64' b*:datastring ')' ')'

We could also choose not to provide such an abbreviation.