Leaving aside the trivialities of specific implementation details¹, what are the fundamental problems a parser must confront and solve²?

Let’s consider the input: 1 + 2 * 3. Suppose a grammar dictates that this input should be structured as 1 + (2 * 3). As a parser reads the input from left to right, it reaches 1 + 2 and recognizes that the next token is *. At this point, it must decide whether to group the preceding part into a single unit or continue. This challenge is independent of how the parser is implemented; it's a universal problem inherent to parsing itself.

In this session, I will highlight several such problems within the parsing domain and explore how different parser implementations try to solve them.