Mercantilism is notorious for treating the world economy as a zero-sum game, wherein the local economy is supposed to benefit when regulations that operate to the detriment of foreign economies are in place. Mercantilist thought is now outdated, and starting with Adam Smith and continuing today, commentators love to point out that the economy is not a zero-sum game.
However economies are large and complex beasts, and the statement "the world economy is not zero-sum" only requires that there exists some part of the world economy that is not zero-sum. So, as a contrived example, the fact that pooling our resources to stop a giant meteor from crashing into Earth is win/win for everyone suffices to show that the world economy is "not zero-sum", but has absolutely no bearing on the day-to-day operation of the world economy under 99.999999% of circumstances. In this way, concepts such as absolute advantage serve to illustrate that the world economy is not inherently zero-sum, but fails to demonstrate the degree to which the economy is not zero-sum.
On a practical level, what are some ways/aspects in which the world economy is zero-sum or approximately zero-sum? For example, access to natural resources such as oil might be considered mostly zero-sum... Norway benefits tremendously from its oil production, and if Switzerland were to capture their oil fields in some way then Switzerland would obtain much of that benefit.