Is it ever right to use ば conditional to mean 'when'?


> 「だっ大丈夫よ、まるちゃんだってわたしたちのタイプだと思うよ、ねぇ」ととし子ちゃんが **なぐさめれば**
> 、「そうだよ。さくらはぼくらの方の仲間だよ」と長山君が笑顔で言い、「そうよ」とたまちゃんが優しくうなずく。  
>  _(When?)_ Toshiko comforted her, saying, "It's alright. I think Maru is our
> kind of person", Nagayama smiled, saying "That's right Sakura is on our
> side" and Tama amiably nodded her head in agreement.

I've only ever seen the ば form used to mean 'if' rather than 'when'. But 'if'
certainly doesn't make sense here. How should I interpret なぐさめれば in this
context?

**Edit:** I understand that in general the distinction between 'when' and 'if'
is a bit blurry in Japansese, but I was under the impression that the ば form
always meant 'provided that...'. The 'when' in this sentence seems to be a
definite 'at/after this point in time something definitely happens'. There
doesn't seem to be any hint of a conditional in it. I would have thought とき
would have been better here. I must be missing something.




From スーパー大辞林:

> ### ば
>
> ③ […] 引き続いて起こる事柄についての，きっかけを表す。…すると。

If I may add more to the quoted definition, this is a particular type of `〜ば`
where it denotes the chronology of a single occurrence (trigger event →
following event), and says nothing about what would happen if the trigger
event were to happen again. To me, this kind of `〜ば` seems more common in
written language, and less likely to be found in spoken language.

The natural translation can either be “then” or “when”, depending on the
context or clause order, e.g. _X happened **then** Y happened_, or _Y happened
**when** X happened_.

Some examples from published books, found on
[少納言](http://www.kotonoha.gr.jp/shonagon/):

  * はっとして見渡せ **ば** 、ほかにも植物が並んでいます。  
_Startled, I looked around, then saw other plants as well._

  * 聞け **ば** 、この教授の学生時代の同級生が例の人事部の佐藤次長であるとのこと。  
_When I asked, I was told this professor's classmate was that assistant
manager Sato from HR._

  * 東京に出れ **ば** 、私の生まれ故郷に足を向けることも多くなった。  
_After coming out to Tokyo, I've been visiting my hometown quite often._




From スーパー大辞林:

> ### ば
>
> ③ […] 引き続いて起こる事柄についての，きっかけを表す。…すると。

If I may add more to the quoted definition, this is a particular type of `〜ば`
where it denotes the chronology of a single occurrence (trigger event →
following event), and says nothing about what would happen if the trigger
event were to happen again. To me, this kind of `〜ば` seems more common in
written language, and less likely to be found in spoken language.

The natural translation can either be “then” or “when”, depending on the
context or clause order, e.g. _X happened **then** Y happened_, or _Y happened
**when** X happened_.

Some examples from published books, found on
[少納言](http://www.kotonoha.gr.jp/shonagon/):

  * はっとして見渡せ **ば** 、ほかにも植物が並んでいます。  
_Startled, I looked around, then saw other plants as well._

  * 聞け **ば** 、この教授の学生時代の同級生が例の人事部の佐藤次長であるとのこと。  
_When I asked, I was told this professor's classmate was that assistant
manager Sato from HR._

  * 東京に出れ **ば** 、私の生まれ故郷に足を向けることも多くなった。  
_After coming out to Tokyo, I've been visiting my hometown quite often._

