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

Question

> 「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.

Answer 1

The conditionals ～たら and と often cross the if/when boundary. In literature, you might see と more often.

Speaking of literature, and I'm glad I looked this up as I was answering, sometimes Classical Japanese forms are used in literature. If we look at the 已然形, perfective form (completed action), and add a ば we get "when." The author may be using this form to elevate their writing a bit.