WikiMath

The {(...)} "expression markup" allows for a variety of string and formatting operations to be performed from within markup. Operations defined by this recipe include substr, ftime, strlen, rand, mod, toupper / tolower, ucfirst, ucwords, pagename and asspaced. Markup expressions can be nested, using the markup {(...(...)...)}.

substr

The "substr" expression extracts portions of a string. The arguments are

1. the string to be processed. Always quote the string to be processed.
2. the initial position of the substring. Note that the initial position argument is zero-based (i.e., the first character is referenced via a "0").
3. the number of characters to extract

 {(substr "PmWiki" 2 3)}
 {(substr "PmWiki" 2)}
 {(substr "{*$Group}" 2)}
 {(substr "PmWiki" 0 1)}
 {(substr "PmWiki" 0 -3)}
 {(substr "PmWiki" -3)}

 Wik
 Wiki
 Wiki
 P
 PmW
 iki

To obtain the last n characters of a string use {(substr "string" -n)}
To truncate the last n characters of a string use {(substr "string" 0 -n)}

ftime

"Ftime" expressions are used for date and time formatting. The generic form is

where fmt is a formatting string and when is the time to be formatted. The arguments can be in either order and may use the optional "fmt=" and "when=" labels.

The "tz" (time zone) argument allows the setting of a different time zone, only available on installations running PHP 5.1 or newer. See the list of supported time zones, any value not found there will be silently ignored.

The "locale" (language locale) argument allows the time format to be printed in a different language for names of weekdays and months, as long as that language locale is available on the server. You can set different locales to try, separated with commas or spaces, for example "fr_FR.utf8,fr_FR,fr". If none of the listed locales is available, the argument is silently ignored.

With international locales, if you see weird characters, try adding or removing the ".utf8" or ".UTF-8" part of the locale, e.g. try both "fr_FR.utf8" and "fr_FR" to see which one works for you. Wikis with UTF-8 enabled are more likely to need the ".utf8" part.

Examples:

 {(ftime)}
 {(ftime fmt="%F %H:%M")}
 {(ftime %Y)}
 {(ftime fmt=%T)}
 {(ftime when=tomorrow)}
 {(ftime fmt="%Y-%m-%d" yesterday)}
 {(ftime "+1 week" %F)}
 {(ftime fmt=%D "+1 month")}
 {(ftime fmt="%a%e %b" when="next week")}
 {(ftime fmt="%A, %d %B %Y, %Hh%M" locale=fr_FR.utf8 tz=Europe/Paris)}

 24/11/2024 13:10
 2024-11-24 13:10
 2024
 13:10:25
 25/11/2024 00:00
 2024-11-23
 2024-12-01
 12/24/24
 Mon25 Nov
 dimanche, 24 novembre 2024, 14h10

The fmt parameter is whatever is given by "fmt=", the first parameter containing a '%', or else the site's default. The formatting codes are described at PHP's strftime function. In addition to those, '%o' produces the ordinal suffix ("st" for 1st), '%F' produces ISO-8601 dates like 2022-10-30, '%s' produces Unix timestamps, and '%L' produces a format like @2022-10-30T01:27:34Z which can be displayed in the timezone of the visitor per Cookbook:LocalTimes.

Some common formatting strings:

     %F                # ISO-8601 dates      "2024-11-24"
     %s                # Unix timestamp      "1732453825"
     %H:%M:%S          # time as hh:mm:ss    "13:10:25"
     %m/%d/%Y          # date as mm/dd/yyyy  "11/24/2024"
     "%A, %B %e%o, %Y" # in words            "Sunday, November 24th, 2024"

Note that if you use an undefined format string such as %q or %E, it will be left unchanged by ftime, but later PmWiki may process it as a WikiStyle which may be unexpected.

The when parameter understands many different date formats. The when parameter is whatever is given by "when=", or whatever parameter remains after determining the format parameter. Some examples:

    2007-04-11            # ISO-8601 dates
    20070411              # dates without hyphens, slashes, or dots
    2007-03               # months
    @1176304315           # Unix timestamps (seconds since 1-Jan-1970 00:00 UTC)
    now                   # the current time
    today                 # today @ 00:00:00
    yesterday             # yesterday @ 00:00:00
    "next Monday"         # relative dates
    "last Thursday"       # relative dates
    "-3 days"             # three days ago
    "+2 weeks"            # two weeks from now

Note: If you want to convert a Unix timestamp you must prefix with the @. Thus, "{(ftime "%A, %B %d, %Y" @1231116927)}".

The when parameter uses PHP's strtotime function to convert date strings according to the GNU date input formats; as of this writing it only understands English phrases in date specifications.

The variable $FTimeFmt can be used to override the default date format used by the "ftime" function. The default $FTimeFmt is $TimeFmt.

strlen

The "strlen" expression returns the length of a string. The first argument is the string to be measured.

 {(strlen "{$:Summary}")}

 32

rand

The "rand" expression returns a random integer. The first argument is the minimum number to be returned and the second argument is the maximum number to be returned. If called without the optional min, max arguments rand() returns a pseudo-random integer between 0 and RAND_MAX. If you want a random number between 5 and 15 (inclusive), for example, use (rand 5 15).

 {(rand)}
 {(rand 1 99)}

 244248640
 22

mod

The advanced "mod" expression returns the modulo (remainder) of the division of two numbers. It may be used in advanced PageList templates together with {$$PageCount} to insert markup every (modulo) entries, for example to create alternate styled "zebra" table rows, or to insert a line/row break. (See also PageLists, WikiStyles and ConditionalMarkup.)

>>comment<<
%define=bg1 item bgcolor=#f88%
%define=bg2 item bgcolor=#ff8%
%define=bg0 item bgcolor=#8f8%[=
[[#altrows]]
* %bg{(mod {$$PageCount} 3)}% {=$Name} ({$$PageCount})
[[#altrowsend]]=]
>><<
(:pagelist fmt=#altrows group=PmWiki count=10:)

toupper / tolower

The "toupper" and "tolower" expressions convert a string into uppercase or lowercase. The first argument is the string to be processed.

 {(toupper "{$:Summary}")}
 {(tolower "{$:Summary}")}

 STRING AND FORMATTING OPERATIONS
 string and formatting operations

ucfirst / ucwords

The "ucfirst" expression converts to uppercase the first character of the string, and "ucwords", the first character of each word. The first argument is the string to be processed.

 {(ucfirst "{$:Summary}")}
 {(ucwords "{$:Summary}")}

 String and formatting operations
 String And Formatting Operations

pagename

The "pagename" expression builds a pagename from a string. The first argument is the string to be processed.

 {(pagename "{$:Summary}")}

 PmWiki.StringAndFormattingOperations

asspaced

The "asspaced" expression formats wikiwords. The first argument is the string to be processed.

 {(asspaced "{$FullName}")}

 Pm Wiki.Markup Expressions

Nesting expressions

Markup expressions can be nested. Omit the curly braces for the inner expressions:

 {(tolower (substr "Hello World" 2))}

 llo world

Notes

• For PmWikis version 2.2.33 or older, the string-processing expressions may not work properly on multibyte UTF-8 characters. Newer versions should work fine.

See also

• Cookbook:MarkupExpressionSamples — custom markup expression samples
• Cookbook:MarkupExprPlus