TLang.Shell

run — Capture Output

Shell.run executes a command, waits for it to complete, and returns stdout as a String. Raises an error if the exit code is non-zero.

      let branch = Shell.run("git rev-parse --abbrev-ref HEAD")
      let log    = Shell.run("git log --oneline -5")
    

Shell.runIn executes in a specified directory.

      let result = Shell.runIn("./gradlew build", "output/myapp")
    

capture — Full Result Map

Shell.capture returns a Map with stdout, stderr, exitCode, and success fields. Does not raise on non-zero exit.

      let result = Shell.capture("java -version")
      let out    = Map.get(result, "stdout")
      let err    = Map.get(result, "stderr")
      let code   = Map.get(result, "exitCode")
      let ok     = Map.get(result, "success")
    

Shell.captureIn runs in a specified directory.

      let result = Shell.captureIn("./gradlew test", "output/myapp")
    

stream — Live Output

Shell.stream runs a command and pipes its output directly to the terminal as it runs. Returns the exit code as an Int. Use this for long-running processes where you want to see progress.

      let code = Shell.stream("./gradlew quarkusDev")
    

Shell.streamIn runs in a specified directory.

      let code = Shell.streamIn("npm run dev", "output/frontend")
    

env and which

      let home  = Shell.env("HOME")       // → String value of env var, or ""
      let java  = Shell.which("java")     // → absolute path, or ""
      let node  = Shell.which("node")
    

Use which to check tool availability before running.

      if (Shell.which("docker") == "") {
          Terminal.println("Docker not found — skipping container build")
      } else {
          Shell.run("docker build -t myapp .")
      }
    

Choosing the Right Function

Use Shell.run when you need the command output as a string for further processing. Use Shell.capture when you need the exit code or stderr, or when failure should not abort the program. Use Shell.stream for interactive or long-running processes that print progress (dev servers, build tools, test runners).

      // Get git branch name for a banner
      let branch = Shell.run("git rev-parse --abbrev-ref HEAD")

      // Run tests — check exit code manually
      let result = Shell.capture("./gradlew test")
      if (Map.get(result, "success") == "false") {
          Terminal.println("Tests failed:\n" + Map.get(result, "stdout"))
      }

      // Start dev server — stream output live
      Shell.streamIn("npm run dev", "frontend")