How to parse 親も辞書を買ってやったかいがあるってもんだ


> 親も辞書を買ってやったかいがあるってもんだよ

The context is that speaker (a child) is trying to find the meaning of a word
and asks her friend if she can borrow a dictionary. The friend ridicules her.
She brushes aside the insults, saying that "dictionary owners know complicated
things" followed by the above sentence.

My previous attempt to translate this sentence was a disaster, so I'm going to
try again. Please help me to understand my errors.

買ってやった is "bought for me"

verbかいがある is "There is value in doing verb"

I think って must be a short hand for と and I'm going to guess that there's an
implicit おもう.

ものだ is one that always confuses me. It seems to be context dependent and since
I'm struggling with the rest of the sentence I'm not in a position to figure
out which one it means.

So here's my new attempt:

> I think it would be worthwhile if my parents had bought me a dictionary too.

I don't like my placement of "too". I don't understand what も is doing
attached to 親.

Maybe:

> My parents also think it would be worthwhile if they bought me a dictionary.

is better. At least も is on the right place for that.




**TL;DR** From the given context, I guess the gist is something like:

> Dictionary owners know complicated things. That really makes parents happy
> they bought their kid a dictionary.

* * *

The following is just my take on this, and I'm sure there are differing views,
so please take it as one of many perspectives.

## “親も”

This is a common use of `〜も`, where it is not really meant as a _specific_
“also” marker. It is used in place of `〜は` as a general topic marker, when
simply using `〜は` may seem too much like a contrast marker.

  * 花子 **は** 大きくなった ( _Hanako has grown taller._ )  
This has this risk of being interpreted as a contrast marker. It can sometimes
feel like you're implying some other person has not grown taller, while Hanako
has.

  * 花子 **も** 大きくなったね ( _Hanako, she's grown taller…_ )  
This can be confusing when you stick to the textbook explanation of the
similarity marker `〜も` (e.g. 太郎は大きくなったし花子も大きくなった). Sometimes, it's not much
more than a simple topic marker. It's often used when stating something as a
sentiment rather than a cold fact, in combination with sentence endings like
〜ねえ, 〜なあ, or 〜よ. Here the person is not drawing similarities with anything
specific, so you shouldn't bend over backwards trying to insert the notion of
an “also/too”.

Examples:

  * 親も大変だね _Tough being a parent, huh._
  * おまえも上手になったな _You've really improved, haven't you._

## “ってもんだ”

This is a colloquial form of 〜というものだ. Adding it to a phrase can have the
effect of turning a singular event into a generalized phenomenon.

For example, let's say a teacher is pleased that his pupil has passed an
entrance exam:

  * 先生「がんばって教えたかいが **あった** 」  
_Teacher: (This outcome makes me feel) It was well worth my effort teaching._

  * 先生「がんばって教えたかいが **あるというものだ** 」  
_Teacher: (These kinds of outcomes make people feel) It was well worth the
effort teaching._

Another example:

  * 少し休めば元気になるよ  
_You'll get better if you rest a little._

  * 少し休めば元気になる **ってもんだ** よ  
_(It's generally the case that) people get better when they rest a little._




**TL;DR** From the given context, I guess the gist is something like:

> Dictionary owners know complicated things. That really makes parents happy
> they bought their kid a dictionary.

* * *

The following is just my take on this, and I'm sure there are differing views,
so please take it as one of many perspectives.

## “親も”

This is a common use of `〜も`, where it is not really meant as a _specific_
“also” marker. It is used in place of `〜は` as a general topic marker, when
simply using `〜は` may seem too much like a contrast marker.

  * 花子 **は** 大きくなった ( _Hanako has grown taller._ )  
This has this risk of being interpreted as a contrast marker. It can sometimes
feel like you're implying some other person has not grown taller, while Hanako
has.

  * 花子 **も** 大きくなったね ( _Hanako, she's grown taller…_ )  
This can be confusing when you stick to the textbook explanation of the
similarity marker `〜も` (e.g. 太郎は大きくなったし花子も大きくなった). Sometimes, it's not much
more than a simple topic marker. It's often used when stating something as a
sentiment rather than a cold fact, in combination with sentence endings like
〜ねえ, 〜なあ, or 〜よ. Here the person is not drawing similarities with anything
specific, so you shouldn't bend over backwards trying to insert the notion of
an “also/too”.

Examples:

  * 親も大変だね _Tough being a parent, huh._
  * おまえも上手になったな _You've really improved, haven't you._

## “ってもんだ”

This is a colloquial form of 〜というものだ. Adding it to a phrase can have the
effect of turning a singular event into a generalized phenomenon.

For example, let's say a teacher is pleased that his pupil has passed an
entrance exam:

  * 先生「がんばって教えたかいが **あった** 」  
_Teacher: (This outcome makes me feel) It was well worth my effort teaching._

  * 先生「がんばって教えたかいが **あるというものだ** 」  
_Teacher: (These kinds of outcomes make people feel) It was well worth the
effort teaching._

Another example:

  * 少し休めば元気になるよ  
_You'll get better if you rest a little._

  * 少し休めば元気になる **ってもんだ** よ  
_(It's generally the case that) people get better when they rest a little._

