-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 12/29/10 22:05 , william murphy wrote:
I've spent a lot of time trying to write a version of concat, which concatenates lists of any "depth": So: concat'' [[[1,2],[3,4]],[[5]]] would return: [1,2,3,4,5]
You can't do that, at least with a normal type signature. There might be some evil that can do it, but (as you found) if you try to do it naively you will get an error which amounts to "this type can't represent both an item and a list of that item at the same time". - -- brandon s. allbery [linux,solaris,freebsd,perl] allbery@kf8nh.com system administrator [openafs,heimdal,too many hats] allbery@ece.cmu.edu electrical and computer engineering, carnegie mellon university KF8NH -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (Darwin) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAk0b+Z0ACgkQIn7hlCsL25WFCQCeNkSf0+1pyJI+rpBWtk3uBsv5 qosAoIRQQyg78IPlHuQiiVleqmYUdQD+ =lOjO -----END PGP SIGNATURE-----