Re: Why does the lexer convert text integer lexemes to binary integers? I thought that lexers should be simple?

George Neuner <gneuner2@comcast.net> schrieb:
> On Fri, 15 Jul 2022 03:02:07 -0700 (PDT), Jan Ziak
><0xe2.0x9a.0x9b@gmail.com> wrote:
>
>>On Friday, July 15, 2022 at 4:13:42 AM UTC+2, George Neuner wrote:
>>> In many (actually most) cases, the binary representation of an integer
>>> can be stored in less space than the text representation.
>>
>>The output of a command such as (cd /usr/src/linux; grep --only-matching
>>--recursive "\b[0-9][0-9]*\b") proves the falsity of the above claim.
>>
>>Binary, fixed-width, representation of integers is statistically more
>>space-efficient compared to implicit-width textual representation only if the
>>text representation of the integers includes (for example): a plain 32/64-bit
>>pointer to the start of the text, a plain 16/32/64-bit relative/absolute
>>offset to the start of the number in a character array, the [length of the
>>textual form of the number] in an explicit form.
>
> ???
>
> Decimal 100 is 3 characters in text, but 1 byte in binary.


... if it is known that the number is in the range that can be
represented by a single byte. If it is stored into a four-byte
integer, 100 takes four bytes (obviously). If there is a length
specification, it might even be longer.


But of course our moderator was right when he wrote


[...]


> but as a message earlier today pointed out,
> it's not likely to make any difference in practical compilers. -John]

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