yiransheng / basic_rs Goto Github PK

Also throwing away pretty much all source info

Example:

10 READ X
20 GOTO 200

Currently producing:

Compile error at Line: 0

Compile failed

Cause is in CFG traversal, the first NEXT takes away for state. Needs to check for index variable.

not proper DFS, visited node might get emitted more than once

Currently, scanner is somewhat spaces insensitive, it can recognize tokens like "L E T".

However, certain cases are not covered, such as "< =".

Do a full audit, and make sure spaces are skipped when needed, and add unit tests for all token types.

Currently LineNo is a type alias to usize.

Should convert it to a new type, as in a couple of places line numbers might get confused with line index.

Perhaps should use petgraph crate to represent the graph, adds a bit overhead, but makes underlying algorithm and analysis clearer.

Find a lib for io, extend VM to accept chunks after init

This will allow interactive programs.

Supporting it in wasm will be tricky, as INPUT is blocking.. maybe use window.confirm for this?

Changes required:

• Update keyword.js to generate new type and compile time DFA for keywords
• Update Token enum
• Update ast data types with new statement type
• Update parser
• Add Statement::Input variant in ir
• Add Input OpCode variant
• Modify VM to take in stdin.lock() in run and exec method
• Handle stdin input, fail on number parsing (add new variant to RuntimeError)
• Use unimplemented!() on wasm side

Later,

Investigate window.confirm approach

EDIT: window.prompt