Programming Perl, 4th Edition

Tracing

T

This command produces a stack backtrace.

t

t EXPR

This command toggles trace mode, which prints out every line in your program as it is evaluated. See also the AutoTrace option discussed later in this chapter. If an EXPR is provided, the debugger will trace through its execution. See also the later section Unattended Execution.

W

W EXPR

This command adds EXPR as a global watch expression. (A watch expression is an expression that will cause a breakpoint when its value changes.) If no EXPR is provided, all watch expressions are deleted.