Feather Programming Language

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info ​

Queries information about the interpreter state.

Syntax ​

tcl
info subcommand ?arg ...?

Subcommands ​

Variables ​

  • info exists varName - Returns 1 if variable exists, 0 otherwise. Handles qualified names (e.g., ::ns::var).
  • info locals ?pattern? - Returns names of local variables matching pattern. Excludes linked variables (global/upvar/variable).
  • info globals ?pattern? - Returns names of global variables matching pattern.
  • info vars ?pattern? - Returns names of all visible variables matching pattern. Namespace-aware pattern matching.

Procedures ​

  • info commands ?pattern? - Returns names of all commands matching pattern. Searches current namespace plus global namespace. Qualified patterns (containing ::) search the specified namespace.
  • info procs ?pattern? - Returns names of user-defined procedures matching pattern. Namespace-aware, excludes builtins.
  • info body procname - Returns the body of a procedure.
  • info args procname - Returns the parameter names of a procedure.
  • info default procname arg varname - Sets varname to default value if arg has one. Returns 1 if default exists, 0 otherwise.

Call Stack ​

  • info level ?number? - Returns current level or command at specified level. Supports relative (negative) and absolute levels.
  • info frame ?number? - Returns dictionary with frame information including: type (proc, source, or eval), cmd, proc, level, file, namespace, line, lambda.

Other ​

  • info script - Returns filename of currently executing script. Note: Unlike TCL, Feather only supports reading the script path, not setting it.
  • info type value - Returns the type name of a value. Feather extension: returns "list", "dict", "int", "double", "string", or the registered type name for foreign objects.
  • info methods value - Returns list of methods available on a foreign object. Feather extension for introspecting foreign object methods.

Pattern Matching ​

All subcommands that accept a pattern use glob-style pattern matching (same as string match). For namespace-aware subcommands like info commands, info procs, and info vars, only the final component of a qualified pattern is treated as a pattern.

Examples ​

Feather Script
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Feather Script
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Feather Script
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Feather Script
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Feather Script
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Feather Script
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Feather Script
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Output

See Also ​