with_flag : 'a ref * 'a -> ('b -> 'c) -> 'b -> 'c
STRUCTURE
Lib
SYNOPSIS
Apply a function under a particular flag setting.
LIBRARY
Lib
DESCRIPTION
An invocation with_flag (r,v) f x sets the reference variable r to the value v, then evaluates f x, then resets r to its original value, and returns the value of f x.
FAILURE
Fails if f x fails. In that case, r is reset to its original value before raising the exception from f x.
EXAMPLE
- fun print_term_nl tm = (print_term tm; print "\n");
> val print_term_nl = fn : term -> unit

- with_flag (show_types, true) print_term_nl (concl T_DEF);
T = ((\(x :bool). x) = (\(x :bool). x))
> val it = () : unit

- print_term_nl (concl T_DEF);
T = ((\(x. x) = (\x. x))
> val it = () : unit

SEEALSO
traces, register_btrace, trace, time
HOL  Kananaskis-14