I understand parsing in contexts like command-line arguments, but I'm not sure what people mean when they say they're parsing a math equation. What kinds of equations require parsing, and what would the process actually involve?
2 Answers
The expression could be something simple like `2 + 3 * 4` or more involved with parentheses, exponents, functions, and variables. Once the text is broken down, a parser can determine that multiplication happens before addition, evaluate the result, or create an expression tree for later use. So “parse” means analyze the notation and its structure, not just pass the string somewhere.
Parsing a math expression means reading its text and breaking it into meaningful pieces so a program can understand it. For example, `1.23 * (456 + 7)` could be split into numbers, operators, and parentheses. A regular expression might help recognize or tokenize those pieces, but that is usually only the first step—not the full parsing process.
Tokenizing produces a stream such as number, multiply, left parenthesis, number, plus, number, right parenthesis. The parser then uses that stream to build a structure that reflects grouping and operator precedence.