X-Git-Url: https://git.exim.org/users/jgh/exim.git/blobdiff_plain/75b1493f48e2212184289338fa4c42941ac8d426..b2d5182ba3c9c24a92edc47d9e4f8bae41c6ca0a:/doc/doc-txt/NewStuff?ds=inline diff --git a/doc/doc-txt/NewStuff b/doc/doc-txt/NewStuff index 04177227d..37368ac4d 100644 --- a/doc/doc-txt/NewStuff +++ b/doc/doc-txt/NewStuff @@ -1,4 +1,4 @@ -$Cambridge: exim/doc/doc-txt/NewStuff,v 1.140 2007/02/07 12:23:35 ph10 Exp $ +$Cambridge: exim/doc/doc-txt/NewStuff,v 1.144 2007/03/13 11:06:48 ph10 Exp $ New Features in Exim -------------------- @@ -292,6 +292,108 @@ Version 4.67 option; with -I they don't. In both cases it is possible to change the case sensitivity within the pattern using (?i) or (?-i). +16. A number of new features have been added to string expansions to make it + easier to process lists of items, typically addresses. These are as + follows: + + * ${addresses:} + + The string (after expansion) is interpreted as a list of addresses in RFC + 2822 format, such as can be found in a To: or Cc: header line. The + operative address (local-part@domain) is extracted from each item, and the + result of the expansion is a colon-separated list, with appropriate + doubling of colons should any happen to be present in the email addresses. + Syntactically invalid RFC2822 address items are omitted from the output. + + It is possible to specify a character other than colon for the output + separator by starting the string with > followed by the new separator + character. For example: + + ${addresses:>& The Boss , sec@base.ment (dogsbody)} + + expands to "ceo@up.stairs&sec@base.ment". Compare ${address (singular), + which extracts the working address from a single RFC2822 address. + + * ${map{}{}} + + After expansion, is interpreted as a list, colon-separated by + default, but the separator can be changed in the usual way. For each item + in this list, its value is place in $item, and then is expanded + and added to the output as an item in a new list. The separator used for + the output list is the same as the one used for the input, but is not + included in the output. For example: + + ${map{a:b:c}{[$item]}} ${map{<- x-y-z}{($item)}} + + expands to "[a]:[b]:[c] (x)-(y)-(z)". At the end of the expansion, the + value of $item is restored to what it was before. + + * ${filter{}{}} + + After expansion, is interpreted as a list, colon-separated by + default, but the separator can be changed in the usual way. For each item + in this list, its value is place in $item, and then the condition is + evaluated. If the condition is true, $item is added to the output as an + item in a new list; if the condition is false, the item is discarded. The + separator used for the output list is the same as the one used for the + input, but is not included in the output. For example: + + ${filter{a:b:c}{!eq{$item}{b}} + + yields "a:c". At the end of the expansion, the value of $item is restored + to what it was before. + + * ${reduce{}{}{}} + + The ${reduce expansion operation reduces a list to a single, scalar string. + After expansion, is interpreted as a list, colon-separated by + default, but the separator can be changed in the usual way. Then + is expanded and assigned to the $value variable. After this, each item in + the list is assigned to $item in turn, and is expanded + for each of them. The result of that expansion is assigned to $value before + the next iteration. When the end of the list is reached, the final value of + $value is added to the expansion string. The ${reduce expansion item can be + used in a number of ways. For example, to add up a list of numbers: + + ${reduce {<, 1,2,3}{0}{${eval:$value+$item}}} + + The result of that expansion would be "6". The maximum of a list of numbers + can be found: + + ${reduce {3:0:9:4:6}{0}{${if >{$item}{$value}{$item}{$value}}}} + + At the end of a ${reduce expansion, the values of $item and $value is + restored to what they were before. + +17. There's a new ACL modifier called "continue". It does nothing of itself, + and processing of the ACL always continues with the next condition or + modifier. It is provided so that the side effects of expanding its argument + can be used. Typically this would be for updating a database. It is really + just a syntactic tidiness, because the following two lines have the same + effect: + + continue = + condition = ${if eq{0}{}{true}{true}} + +18. It is now possible to use newline and other control characters (those with + values less than 32, plus DEL) as separators in lists. Such separators must + be provided literally at the time the list is processed, but the string + expansion that happens first means that you can write them using normal + escape sequences. For example, if a new-line separated list of domains is + generated by a lookup, you can now process it directly by a line such as + this: + + domains = <\n ${lookup mysql{.....}} + + This avoids having to change the list separator in such data. Unlike + printing character separators, which can be included in list items by + doubling, it is not possible to include a control character as data when it + is set as the separator. Two such characters in succession are interpreted + as enclosing an empty list item. + +19. The exigrep utility now has a -v option, which inverts the matching + condition. + Version 4.66 ------------