と details

write + whenever

kaku to

whenever; when — one thing automatically brings the next

meaning: whenever you write

このボタンを押すおすと、切符きっぷが出でてきます。

kono botan o osu to, kippu ga dete kimasu.

A ticket comes out whenever you press this button. neutral

ドアを開あけると、知しらない猫ねこが座すわっていた。

doa o akeru to, shiranai neko ga suwatte ita.

When I opened the door, an unfamiliar cat was sitting there. neutral

Examples

whenever / when — an automatic or invariable consequence

このボタンを押おすと、切符きっぷが出でてきます。

kono botan o osuto, kippu ga dete kimasu.

A ticket comes out whenever you press this button. neutral

この窓まどを開あけると、風かぜがすごく入はいってくるよ。

kono mado o akeruto, kaze ga sugoku haitte kuru yo.

A ton of wind comes in whenever you open this window. casual

春はるになると、この辺へんは観光客かんこうきゃくだらけになるよ。

haru ni naru to, kono hen wa kankoukyaku darake ni naru yo.

Come spring, this area gets packed with tourists. casual

when — narrative discovery, did X and there was Y

ドアを開あけると、知しらない猫ねこが座すわっていた。

doa o akeru to, shiranai neko ga suwatte ita.

When I opened the door, an unfamiliar cat was sitting there. neutral

This is the と inside ないといけない — "if you don't, it won't do" — which is why clipped 行かないと。 still reads as obligation.

ば
と states an automatic, exceptionless consequence — machines, routes, habits — and bars commands, requests, and invitations from its main clause outright; ば shades hypothetical and hosts them freely when its own clause is stative (時間があれば来てください).

という
Identical と, opposite parse, and what follows decides it — ドアを開けると言った is quotative (said he'd open it), ドアを開けると寒い is conditional (when you open it, it's cold); only the quotative と can relax to って.