Pretty_print woes

Ruby
1

I like the formatting one gets by

require ‘pp’
pp foo() # etc.

In my application however, I don’t want the pp-formatted string to be
printed, but to be returned as a string to my application. Searching
the Net, I came up with the following solution (Example):

require ‘pp’
…
result=foo(bar)
$my_message=“The function call foo(”+
bar.pretty_print_inspect+
") returned: "+result.pretty_print_inspect

This works well most of the time, for example if the values formatted
with pretty_print_inspect are arrays or numbers. I get, however, a
runtime error when calling for String:

“abc”.pretty_print_inspect
RuntimeError: pretty_print is not overridden for String

Is there a different way to use the module pp, so that its output goes
to a string?

Ronald

2

On 28.06.2007 13:31, Ronald F. wrote:

…
RuntimeError: pretty_print is not overridden for String

Is there a different way to use the module pp, so that its output goes
to a string?

Ronald

irb(main):009:0> puts “foo"bar”.pretty_inspect
“foo"bar”
=> nil

robert

3

runtime error when calling for String:

“abc”.pretty_print_inspect
RuntimeError: pretty_print is not overridden for String

Is there a different way to use the module pp, so that its
output goes
to a string?
irb(main):009:0> puts “foo"bar”.pretty_inspect
“foo"bar”
=> nil

Thanks a lot! Nearly perfect!! (Actually, I use pretty_inspect.chomp,
because pretty_inspect adds a \n to the formatted string).

Ronald

4

On Jun 28, 2007, at 8:26 AM, Ronald F. wrote:

runtime error when calling for String:

Thanks a lot! Nearly perfect!! (Actually, I use pretty_inspect.chomp,
because pretty_inspect adds a \n to the formatted string).

Ronald

Actually, puts is adding that \n to the string, but your result is
what you wanted!

5

On 28.06.2007 15:42, John J. wrote:

This works well most of the time, for example if the values
irb(main):009:0> puts “foo"bar”.pretty_inspect
“foo"bar”
=> nil

Thanks a lot! Nearly perfect!! (Actually, I use pretty_inspect.chomp,
because pretty_inspect adds a \n to the formatted string).

Ronald

Actually, puts is adding that \n to the string, but your result is what
you wanted!

No, #pretty_inspect actually adds it:

irb(main):001:0> “a”.pretty_inspect
=> ““a”\n”

Ronald, #pretty_inspect can actually add newlines itself:

irb(main):004:0> ha=(1…10).inject({}) {|h,i| h[i] = Array.new(i, i); h}
=> {5=>[5, 5, 5, 5, 5], 6=>[6, 6, 6, 6, 6, 6], 1=>[1], 7=>[7, 7, 7, 7,
7, 7, 7], 2=>[2, 2], 8=>[8, 8, 8, 8, 8, 8, 8, 8],
3=>[3, 3, 3], 9=>[9, 9, 9, 9, 9, 9, 9, 9, 9], 4=>[4, 4, 4, 4],
10=>[10, 10, 10, 10, 10, 10, 10, 10, 10, 10]}
irb(main):005:0> ha.pretty_inspect
=> “{5=>[5, 5, 5, 5, 5],\n 6=>[6, 6, 6, 6, 6, 6],\n 1=>[1],\n 7=>[7, 7,
7, 7, 7, 7, 7],\n 2=>[2, 2],\n 8=>[8, 8, 8, 8, 8
, 8, 8, 8],\n 3=>[3, 3, 3],\n 9=>[9, 9, 9, 9, 9, 9, 9, 9, 9],\n 4=>[4,
4, 4, 4],\n 10=>[10, 10, 10, 10, 10, 10, 10, 10,
10, 10]}\n”
irb(main):006:0> puts ha.pretty_inspect
{5=>[5, 5, 5, 5, 5],
6=>[6, 6, 6, 6, 6, 6],
1=>[1],
7=>[7, 7, 7, 7, 7, 7, 7],
2=>[2, 2],
8=>[8, 8, 8, 8, 8, 8, 8, 8],
3=>[3, 3, 3],
9=>[9, 9, 9, 9, 9, 9, 9, 9, 9],
4=>[4, 4, 4, 4],
10=>[10, 10, 10, 10, 10, 10, 10, 10, 10, 10]}
=> nil
irb(main):007:0>

Kind regards

robert