Interpreters vs. Compilers
Both start from the same source text, but they diverge at a fork: translate everything upfront and execute native code, or walk the program while it runs. This video follows both paths through the frontend and beyond — lexer, parser, AST, then either codegen or a tree-walking/bytecode loop — and shows why modern languages refuse to pick a side.
Topics covered:
- The shared frontend: lexing, parsing, and building the AST
- The compiler path: codegen, object files, linking, and what the CPU finally runs
- The interpreter path: walking the AST or executing bytecode in a VM loop
- Why bytecode is the compromise: portable, compact, and fast to interpret
- Dispatch overhead: why interpreter loops are slow and how switch-dispatch helps
- The blur: bytecode VMs with JITs, transpilers, and source-to-source compilers
- How Python, Java, and JavaScript each split the difference in practice
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