Scenario 1

cd $path

1. Set $OLDPWD to the current value of the $PWD.
2. Set $PWD to the current value of $path.

Scenario 2

cd -

1. Set $PWD to the current value of $OLDPWD.
2. Print $PWD.

• Implement the POSIX jobs command
• Implement the POSIX fg command
• Invoking a <block> with <block> & executes <block> in a background job

Should be able to pattern match on $args in functions.

Expression <a>..<b> should be parsed into Expr::Range(a, b). Evaluating the range results in a vector of elements from <a> (inclusive) to <b> (exclusive).

Support basic execution of commands, as in bash and pwsh.

• .oym files are oysterlang module files
  • Only pub assignments are exported
  • Only pub $main = ... is invoked if the module is invoked
• .oys files are oyster script files without exports
• use works same as Rust

$name and $(...) should be expanded in strings and compiled down to Expr::Add(...)

• Support for JSON/Rust syntax for data structures
  • Arrays
  • Hashes
  • String
  • Number
  • Null
• fromjson cmd for parsing stdin into data structures

  $data = $json | fromjson

• tojson cmd for piping to JSON

  $json = $data | tojson

These should work already. Just need basic unit tests to validate.

Support

• Token positions
• Contextual tokenization, such as to allow unquoted strings as parameters