tkcon: `observe` procedure |

Documentation | Purpose & Features | Limitations | To Do | License
--- | --- | --- | --- | ---
Online Demo (requires Tk plugin) | Using TkCon with other Tk Languages

Getting Started | Special Bindings | Procedures | Screenshot
--- | --- | --- | ---
`dump` | `tkcon` | `idebug` | `observe`

This command provides runtime debugging output for variables and commands without the need to edit your code. For variables, the underlying mechanism uses `trace` and `dump var`. For commands, it renames the observed procedure and uses a special wrapper procedure. WARNING: using this procedure after checkpointing state will result in major problems if you clean state because the renamed (true) commands will be lost.

This procedure is experimental. Comments are encouraged.

`observe command` cmdname ?maxlevel?
  This will create a wrapper command which prints out (using `dump`) the call stack to the console. maxlevel represents the maximum number of levels of the call stack which will be printed (defaults to 4).
`observe cdelete` cmdname
  Removes the wrapper around an observed command.
`observe cinfo` cmdname
  Prints out useless info.
`observe variable` varname operation ?args?
  Currently a wrapper around trace that uses `dump` to print out the value of the named variable whenever the specified operation on that variable occurs (must be read, write or unset).
`observe vdelete` varname operation
  Deletes the trace wrapper around the named variable.
`observe vinfo` varname
  Prints out trace info about the named variable.