Hah! That would be a good reason! :-) And re-reading the *Specification* I now spot it saying "The string must consist entirely of decimal digits." (Sigh!)
I was led astray because when I searched with Google I didn't find mention of Base62 only converting numbers, and indeed I found a web page to convert arbitrary text to Base 62. Hmm… I wonder if it's only Exim's implementation of the base62 expansion operator that imposes the numeric-only requirement, rather than the method as a whole? Cheers and apologies, Mike B-) On 19 October 2016 at 13:27, Felipe Gasper <fel...@felipegasper.com> wrote: > base62 only encodes numerals, though. > > -FG > > > On Oct 19, 2016, at 4:16 AM, Mike Brudenell <mike.bruden...@york.ac.uk> > wrote: > > > > Or perhaps just use Exim's existing base62 and base62d expansion > operators? > > :-) > > > > http://www.exim.org/exim-html-current/doc/html/spec_html/ch- > string_expansions.html#SECTexpop > > > > > > These: > > > > - use the character set [A-Za-z0-9] on case-sensitive systems; > > - use base36 encoding using [A-Z0-9] instead on systems with > > case-insensitive file names; > > - are used by Exim to generate its message identifiers, and hence > > (presumably safe!) file names to store message data in the file system. > > > > Cheers, > > Mike B-) > > > > > > On 18 October 2016 at 22:21, Phil Pennock <exim-us...@spodhuis.org> > wrote: > > > >> On 2016-10-18 at 08:28 +0200, Arkadiusz Miśkiewicz wrote: > >>> On Monday 17 of October 2016, Phil Pennock wrote: > >>>> Or base64-encode it. > >>> > >>> "/" is part of base64 alphabet, so would have to replace that with > other > >>> character, too. > >> > >> You're quite right. I was thinking of the `base64url` encoding from > >> RFC4648; it's used so often that I forgot. > > > > > > -- > > Systems Administrator & Change Manager > > IT Services, University of York, Heslington, York YO10 5DD, UK > > Tel: +44-(0)1904-323811 > > > > Web: www.york.ac.uk/it-services > > Disclaimer: www.york.ac.uk/docs/disclaimer/email.htm > > -- > > ## List details at https://lists.exim.org/mailman/listinfo/exim-users > > ## Exim details at http://www.exim.org/ > > ## Please use the Wiki with this list - http://wiki.exim.org/ > > > -- > ## List details at https://lists.exim.org/mailman/listinfo/exim-users > ## Exim details at http://www.exim.org/ > ## Please use the Wiki with this list - http://wiki.exim.org/ > -- Systems Administrator & Change Manager IT Services, University of York, Heslington, York YO10 5DD, UK Tel: +44-(0)1904-323811 Web: www.york.ac.uk/it-services Disclaimer: www.york.ac.uk/docs/disclaimer/email.htm -- ## List details at https://lists.exim.org/mailman/listinfo/exim-users ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://wiki.exim.org/