/usr/share/doc/libtext-sprintfn-perl/README is in libtext-sprintfn-perl 0.08-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 | SYNOPSIS
use Text::sprintfn; # by default exports sprintfn() and printfn()
# with no hash, behaves just like printf
printfn '<%04d>', 1, 2; # <0001>
# named parameter
printfn '<%(v1)-4d>', {v1=>-2}; # <-2 >
# mixed named and positional
printfn '<%d> <%(v1)d> <%d>', {v1=>1}, 2, 3; # <2> <1> <3>
# named width
printfn "<%(v1)(v2).1f>", {v1=>3, v2=>4}; # < 3>
# named precision
printfn "<%(v1)(v2).(v2)f>", {v1=>3, v2=>4}; # <3.0000>
DESCRIPTION
This module provides sprintfn() and printfn(), which are like sprintf()
and printf(), with the exception that they support named parameters
from a hash.
FUNCTIONS
sprintfn $fmt, \%hash, ...
If first argument after format is not a hash, sprintfn() will behave
exactly like sprintf().
If hash is given, sprintfn() will look for named parameters in argument
and supply the values from the hash. Named parameters are surrounded
with parentheses, i.e. "(NAME)". They can occur in format parameter
index:
%2$d # sprintf version, take argument at index 2
%(two)d # $ is optional
%(two)$d # same
or in width:
%-10d # sprintf version, use (minimum) width of 10
%-(width)d # like sprintf, but use width from hash key 'width'
%(var)-(width)d # format hash key 'var' with width from hash key 'width'
or in precision:
%6.2f # sprintf version, use precision of 2 decimals
%6.(prec)f # like sprintf, but use precision from hash key 'prec'
%(width).(prec)f
%(var)(width).(prec)f
The existence of formats using hash keys will not affect indexes of the
rest of the argument, example:
sprintfn "<%(v1)s> <%2$d> <%d>", {v1=>10}, 0, 1, 2; # "<10> <2> <0>"
Like sprintf(), if format is unknown/erroneous, it will be printed
as-is.
There is currently no way to escape ")" in named parameter, e.g.:
%(var containing ))s
printfn $fmt, ...
Equivalent to: print sprintfn($fmt, ...).
RATIONALE
There exist other CPAN modules for string formatting with named
parameter support. Two of such modules are String::Formatter and
Text::Sprintf::Named. This module is far simpler to use and retains all
of the features of Perl's sprintf() (which we like, or perhaps hate,
but nevertheless are familiar with).
String::Formatter requires you to create a new formatter function
first. Text::Sprintf::Named also accordingly requires you to
instantiate an object first. There is currently no way to mix named and
positional parameters. And you don't get the full features of
sprintf().
HOW IT WORKS
Text::sprintfn works by converting the format string into sprintf
format, i.e. replacing the named parameters like %(foo)s to something
like %11$s.
DOWNSIDES
Currently the main downside is speed. sprintfn() is about 2-3 orders of
magnitude slower than sprintf(). A sample benchmark:
# COMMAND: perl devscripts/bench
TIPS AND TRICKS
Common mistake 1
Writing
%(var)
instead of
%(var)s
Common mistake 2 (a bit more newbish)
Writing
sprintfn $format, %hash, ...;
instead of
sprintfn $format, \%hash, ...;
Alternative hashes
You have several hashes (%h1, %h2, %h3) which should be consulted for
values. You can either merge the hash first:
%h = (%h1, %h2, %h3); # or use some hash merging module
printfn $format, \%h, ...;
or create a tied hash which can consult hashes for you:
tie %h, 'Your::Module', \%h1, \%h2, \%h3;
printfn $format, \%h, ...;
SEE ALSO
sprintf() section on perlfunc
String::Formatter
Text::Sprintf::Named
|