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Comment by seasoup | Hacker News Reader

>> There is no implicit type conversion between numeric, string or boolean types.

>Ok. This is a good thing. Auto conversion is bad.

One of the things I really dislike about developing in Ruby is that I can't do

value = 5 "The value is " + 5

I get bitten by this at least 10 times a day while developing, usually either when dumping to the log, or writing into html. I can fix the problem really quickly now, but every time I get an error:

"r" + 5 "TypeError: can't convert Fixnum into String"

I think, yes, yes you can easily convert a Fixnum into a String.

"r" + 5.to_s

It just means I have to sprinkle .to_s everywhere in my code. Ridiculous!

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please can you explain what

    value = 5 "The value is " + 5

is supposed to do? at the moment i can't work out why it would be frustrating to be unable to type something that looks like a syntax error... (i'm assuming it has some meaning in a language i don't know, which i guess would mean php).

edit: what does "say" mean in the reply below? print? evaluate? and does "later" mean in another statement? or replacing what was before?

He means that he can't say “value = 5” and then later say “"the value is " + 5”.

The problem is that his two lines of code got joined by HN's formatter (which needs two newlines for a real line break). Presumably his desired message was:

value = 5

"The value is " + 5

I see that as a feature. It looks like you're saying "I want to add numbers and letters together and Ruby complains."

If you really want that value in your string, why not use "The value is #{value}"

Maybe they're afraid the translation team will be overly grateful?

Appending doesn't work for translation: not all languages will have the object at the end of the sentence. Better to stick with format strings.

That's what I meant...

Just use inline implicit conversion: "r #{5+3/2}"

It's a lot more typing. :)

If one really wanted that kind of behavior (and not getting errors when trying to add strings and number) you could make it so:

    class String
      def +(o)
        warn "You are adding a #{o.class} to a string." unless o.is_a? String
        "#{self}#{o}"
      end
    end

for example.

Whether this leads to other issues is left as an exercise for the reader and whomever ends up maintaining the reader's code.

    "r#{5}"

or in actual use something like

    "I have #{me.num_of_children}\n"

much better then Auto conversion In python

    "I have " + str(me.num_of_sons) + "and " + str(me.num_of_daughters) +"\n"

does get annoying

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