Revert "Add serialization proposal"

This reverts commit 17af553.

exploration/number-selection.md

@@ -548,92 +548,9 @@ and they _might_ converge on some overlap that users could safely use across pla
 
 ### Standardize the Serialization Forms
 
-Modify the above exact match as follows.
-Note that this implementation is less restrictive than before, but still leaves some
-values that cannot be matched.
-
-> [!IMPORTANT]
-> The exact behavior of exact literal match is only defined for
-> a specific range of numeric values and does not support scientific notation.
-> Very large or very small numeric values will be difficult to perform
-> exact matching on.
-> Avoid depending on these types of keys in message selection.
-
-> [!IMPORTANT]
-> For implementations that do not have arbitrary precision numeric types
-> or operands that do not use these types,
-> it is possible to specify a key value that exceeds the precision
-> of the underlying type.
-> Such a key value will not work reliably or may not work at all
-> in such implementations.
-> Avoid depending on such keys values in message selection.
-
-Number literals in the MessageFormat 2 syntax use a subset of the 
-[format defined for a JSON number](https://www.rfc-editor.org/rfc/rfc8259#section-6).
-The resolved value of an `operand` exactly matches a numeric literal `key`
-if, when the `operand` is serialized using this format
-the two strings are equal.
-
-```abnf
-number   = [ "-" ] int [ fraction ]
-integer  = "0" / [ "-" ] (digit19 *DIGIT)
-int      = "0" / (digit19 *DIGIT)
-digit19  = %31-39 ; 1-9
-fraction = "." 1*DIGIT
-```
-
-If the function `:integer` is used or the `maximumFractionDigits` is 0,
-the production `integer` is used and any fractional amount is omitted,
-otherwise the `minimumFractionDigits` number of digits is produced,
-zero-filled as needed.
-
-The implementation applies the `maximumSignificantDigits` to the value
-being serialized.
-This might involve locally-specific rounding.
-The `minimumSignificantDigits` has no effect on the value produced for comparison.
-
-The option `signDisplay` has no effect on the value produced for comparison.
-
-> [!NOTE]
-> Implementations are not expected to implement this exactly as written,
-> as there are clearly optimizations that can be applied.
-
-> Here are some examples:
-> ```
-> .input {$num :integer}
-> .match $num
-> 0    {{The number 0}}
-> 1    {{The number 1}}
-> -1   {{The number -1}}
-> 1.0  {{This cannot match}}
-> 1.1  {{This cannot match}}
-> ```
-> ```
-> .input {$num :number maximumFractionDigits=2 minimumFractionDigits=2}
-> .match $num
-> 0      {{This does not match}}
-> 0.00   {{This matches the value 0}}
-> 0.0    {{This does not match}}
-> 0.000  {{This does not match}}
-> ```
-> ```
-> .input {$num :number minimumFractionDigits=2 maximumFractionDigits=5}
-> .match $num
-> 0.12       {{Matches the value 0.12}
-> 0.123      {{Matches the value 0.123}}
-> 0.12345    {{Matches the values 0.12345}}
-> 0.123456   {{Does not match}}
-> 0.12346    {{May match the value 0.123456 depending on local rounding mode?}}
-> ```
-> ```
-> .input {$num :number}
-> -0    {{Error: Bad Variant Key}}
-> -99   {{The value -99}}
-> 1111111111111111111111111111 {{Might exceed the size of local integer type, but is valid}}
-> 11111111111111.1111111111111 {{Might exceed local floating point precision, but is valid}}
-> 1.23e-37 {{Error: Bad Variant Key}}
-> ```
-
+Using the design above, remove the integer-only and no-sig-digits restrictions from LDML45
+and specify numeric matching by specifying the form of matching `key` values.
+Comparison is as-if by string comparison of the serialized forms, just as in LDML45.
 
 ### Compare numeric values