[Bug] assigning to string slice causes not implemented: strings do not exist on ASG level

[0rphon]

🐛 Bug Report

Code snippet to reproduce

function main() {
    let x = "hello world";
    x[..2] = "ab";
}

Stack trace & error message

D:\Work\leo-playground>D:\Work\leo_repos\leo\target\release\leo clean && D:\Work\leo_repos\leo\target\release\leo run
      Done Finished in 0 milliseconds 

     Build Starting...
     Build Compiling main program... ("D:\\Work\\leo-playground\\src/main.leo")
thread 'main' panicked at 'not implemented: strings do not exist on ASG level', asg\src\expression\constant.rs:224:17
stack backtrace:
   0: std::panicking::begin_panic_handler
             at /rustc/2fd73fabe469357a12c2c974c140f67e7cdd76d0\/library\std\src\panicking.rs:493
   1: core::panicking::panic_fmt
             at /rustc/2fd73fabe469357a12c2c974c140f67e7cdd76d0\/library\core\src\panicking.rs:92
   2: <leo_asg::expression::constant::Constant as leo_asg::node::FromAst<leo_ast::expression::value::ValueExpression>>::from_ast
   3: <&leo_asg::expression::Expression as leo_asg::node::FromAst<leo_ast::expression::Expression>>::from_ast
   4: leo_asg::statement::assign::<impl leo_asg::node::FromAst<leo_ast::statements::assign::AssignStatement> for &leo_asg::statement::Statement>::from_ast
   5: <&leo_asg::statement::Statement as leo_asg::node::FromAst<leo_ast::statements::statement::Statement>>::from_ast
   6: <leo_asg::statement::block::BlockStatement as leo_asg::node::FromAst<leo_ast::statements::block::Block>>::from_ast
   7: leo_asg::program::function::Function::fill_from_ast
   8: leo_asg::program::Program::new
   9: leo_compiler::compiler::Compiler<F,G>::parse_program
  10: leo_compiler::compiler::Compiler<F,G>::parse_program_with_input
  11: <leo::commands::build::Build as leo::commands::Command>::apply
  12: leo::commands::Command::execute
  13: leo::commands::Command::execute
  14: leo::commands::Command::execute
  15: leo::commands::Command::try_execute
  16: snarkvm_algorithms::snark::groth16::VerifyingKey<E>::write
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

Your Environment

• leo commit c33facb
• rustc version 1.53.0-nightly
• Windows 10.0.19042 (Windows 10 Pro) [64-bit]

[bendyarm]

Can you explain a little? The program looks fine to me, so if it doesn't compile that would be a bug. Also, why does the title talk about ASGs?

[0rphon]

@bendyarm i named the title exactly what the panic says. thread 'main' panicked at 'not implemented: strings do not exist on ASG level'. ill adjust the tags appropriately

[0rphon]

my bad, i was under the impression that this was just complaining about unimplemented behavior. Ive updated everything to reflect that its a bug instead