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I think the argument here is that parsing of the string '1e-300' maybe should be context dependent. In this case, 1e-300 is being parsed as a double, and then forwarded to the function. Maybe it could be parsed as a bigfloat whenever it is an argument of a function expecting a bigfloat.

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Yes, I got that argument, and that is exactly what I was arguing against. You cannot and should not parse the literal double `1e-300` differently dependent on which function it is later passed to. This is what `big"1e-300"` or `BigFloat("1e-300")` is for, where the BigFloat constructor parses the string.

Julia does this for exponentiation, i.e. a literal exponent is parsef differently that exponentiation by a variable.

I think it was a mistake. Invariably, a new user discovers the discrepancy and is thoroughly confused. Let's not repeat the same mistake with big nums.

I don't think this has anything to do with whether 1e-300 and 10.0^-300 is parsed differently (and perhaps that is a mistake). The poster seems to want to parse 1e-300 directly as a BigFloat in the call `BigFloat(1e-300)`, because of the function it is passed to.

Yeah what I mean is - we already have "magic parsing" with literal_pow, and it's confusing and unnecessary. It was a mistake. We should not make the same mistake when parsing float literals

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