Certain queries cause rink to hang

[tiffany352]

• Tim
• Tm

certain variations are fine though:

• Tim to ms
• kTm
• Tm to ms

happens in both web and cli

[Goorzhel]

For me (on NixOS), not a hang but a stack overflow

``` ❯ git rev-parse HEAD 4a492c64f33f51a89a685d31365042d21cb4f0ed ❯ rustc --version rustc 1.72.1 (d5c2e9c34 2023-09-13) ❯ cargo r <<< kTm Finished dev [unoptimized + debuginfo] target(s) in 0.66s warning: the following packages contain code that will be rejected by a future version of Rust: ubyte v0.10.1 note: to see what the problems were, use the option `--future-incompat-report`, or run `cargo report future-incompatibilities --id 1` Running `target/debug/rink` 2 minute, 53.61111 second (time) ❯ cargo r -q <<< Tim thread 'main' has overflowed its stack fatal runtime error: stack overflow zsh: abort (core dumped) cargo r -q <<< Tim ❯ coredumpctl dump rink PID: 2089800 (rink) UID: 1000 (ag) GID: 100 (users) Signal: 6 (ABRT) Timestamp: Sat 2023-09-23 21:19:39 PDT (18s ago) Command Line: target/debug/rink Executable: /tmp/rink-rs/target/debug/rink Control Group: /user.slice/user-1000.slice/session-46.scope Unit: session-46.scope Slice: user-1000.slice Session: 46 Owner UID: 1000 (ag) Boot ID: 6f9d3a176f324fb79b25c56acc661dfd Machine ID: Hostname: Storage: /var/lib/systemd/coredump/core.rink.1000.6f9d3a176f324fb79b25c56acc661dfd.2089800.1695529179000000.zst (present) Size on Disk: 1.2M Message: Process 2089800 (rink) of user 1000 dumped core. Module /tmp/rink-rs/target/debug/rink without build-id. Module /tmp/rink-rs/target/debug/rink Module libgcc_s.so.1 without build-id. Stack trace of thread 2089800: #0 0x00007ffff77c1a8c __pthread_kill_implementation (libc.so.6 + 0x87a8c) #1 0x00007ffff7772c86 raise (libc.so.6 + 0x38c86) #2 0x00007ffff775c8ba abort (libc.so.6 + 0x228ba) #3 0x000055555642b677 n/a (/tmp/rink-rs/target/debug/rink + 0xed7677) ELF object binary architecture: AMD x86-64 ```

I assumed Tm was supposed to mean "terameters" until I read about Tims and thullium. What should rink do in this situation?

[tiffany352]

The issue turned out to be a stack overflow in the code that turns expressions into strings. The definition of Tim is 12^-4 hour and it was getting into infinite recursion on the -4 part. I'll put out a patch version soon with this fix included.