Meaning of 何とやら in this sentence


> 私は勝負日の前日は大抵眠れません。遠足前の何とやらです。気が弱いです。

According to Kenkyusha dictionary, 何とやら means `etc.` or `and so on`. Could it
mean `same` here? My attempt:

> I can hardly sleep the day before a competition. The same goes for
> excursions. It's that I am fainthearted.




何とやら is a placeholder (like "you-know-what(/who)", or
"what's-his(/her/its)-name"), used in place of names you can't remember, or
words and phrases you don't want to mention explicitly.

Notably it has a distinct use as a replacement for a part (often the latter
part) of established expressions, like proverbs and idioms. （Examples:
「ちりも積もれば何とやら (for 山となる)」, 「枯れ木も山の何とやら (for 賑わい)」, 「触らぬ神に何とやら (for 祟りなし)」. I
think the reason for its employment, most of the time, is the psychology "The
less said of a cliche, the better," rather than economy, forgetfulness, or
polite euphemism.)

In this case the idiom (of sorts) they had in mind was probably "遠足前の小学生", a
variation of the more accurate "遠足前日の小学生" - "a grade school kid on the eve of
a field trip" - used for when you are too excited about the next day's event
to go to sleep. (Or less likely "遠足前(日)症候群", which refers to the same thing.)

My translation effort:

> "I can rarely sleep the day before a competition - the proverbial kid on the
> eve of a field trip. I'm weak-nerved."




何とやら is used here for vaguely mentioning something, like 何とかかんとか and so on. It
is used especially for avoiding fully stating something.

Here, 遠足前の何とやら points to an episode that 遠足前は興奮して眠れない (We get excited and
can't sleep well before excursions). The speaker may be intentionally
shortening it by using 何とやら for some reason.

