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diff --git a/docs/users_guide/ghci.xml b/docs/users_guide/ghci.xml
index bde1648..3ba2012 100644
--- a/docs/users_guide/ghci.xml
+++ b/docs/users_guide/ghci.xml
@@ -393,9 +393,9 @@ Prelude>
Show
- The automatic printing of binding results can be supressed with
+ The automatic printing of binding results can be suppressed with
(this does not
- supress printing the result of non-binding statements).
+ suppress printing the result of non-binding statements).
.
You might want to do this to prevent the result of binding
statements from being fully evaluated by the act of printing
@@ -929,6 +929,7 @@ right :: [a]
left:
+[qsort.hs:2:15-46] *Main> :set -fprint-evld-with-show
[qsort.hs:2:15-46] *Main> :print left
left = (_t1::[a])
@@ -948,6 +949,13 @@ left = (_t1::[a])
underscore, in this case
_t1.
+ The flag -fprint-evld-with-show instructs
+ :print to reuse
+ available Show instances when possible. This happens
+ only when the contents of the variable being inspected
+ are completely evaluated.
+
+
If we aren't concerned about preserving the evaluatedness of a
variable, we can use :force instead of
:print. The :force command
@@ -1017,6 +1025,7 @@ right :: [a]
The execution continued at the point it previously stopped, and has
now stopped at the breakpoint for a second time.
+
Setting breakpoints
@@ -1106,10 +1115,14 @@ right :: [a]
Single-stepping is a great way to visualise the execution of your
program, and it is also a useful tool for identifying the source of a
- bug. The concept is simple: single-stepping enables all the
- breakpoints in the program and executes until the next breakpoint is
- reached, at which point you can single-step again, or continue
- normally. For example:
+ bug. GHCi offers two variants of stepping. Use
+ :step to enable all the
+ breakpoints in the program, and execute until the next breakpoint is
+ reached. Use :steplocal to limit the set
+ of enabled breakpoints to those in the current top level function.
+ Similarly, use :stepmodule to single step only on
+ breakpoints contained in the current module.
+ For example:
*Main> :step main
@@ -1118,10 +1131,11 @@ _result :: IO ()
The command :step
- expr begins the evaluation of
+ expr begins the evaluation of
expr in single-stepping mode. If
- expr is ommitted, then it single-steps from
- the current breakpoint.
+ expr is omitted, then it single-steps from
+ the current breakpoint. :stepover
+ works similarly.
The :list command is particularly useful when
single-stepping, to see where you currently are:
@@ -1330,9 +1344,13 @@ a :: a
:trace and :history to establish
the context. However, head is in a library and
we can't set a breakpoint on it directly. For this reason, GHCi
- provides the flag -fbreak-on-exception which causes
- the evaluator to stop when an exception is thrown, just as it does when
- a breakpoint is hit. This is only really useful in conjunction with
+ provides the flags -fbreak-on-exception which causes
+ the evaluator to stop when an exception is thrown, and
+ -fbreak-on-error, which works similarly but stops only on
+ uncaught exceptions. When stopping at an exception, GHCi will act
+ just as it does when a breakpoint is hit, with the deviation that it
+ will not show you any source code location. Due to this, these
+ commands are only really useful in conjunction with
:trace, in order to log the steps leading up to the
exception. For example:
@@ -1662,17 +1680,20 @@ $ ghci -lm
- :browse*module ...
+ :browse*module ...
:browseDisplays the identifiers defined by the module
module, which must be either
- loaded into GHCi or be a member of a package. If the
- * symbol is placed before the module
- name, then all the identifiers defined
- in module are shown; otherwise
- the list is limited to the exports of
+ loaded into GHCi or be a member of a package. If
+ module is omitted, the most
+ recently-loaded module is used.
+
+ If the * symbol is placed before
+ the module name, then all the
+ identifiers in scope in module are
+ shown; otherwise the list is limited to the exports of
module. The
*-form is only available for modules
which are interpreted; for compiled modules (including
@@ -1739,7 +1760,7 @@ $ ghci -lm
Generates a “tags” file for Vi-style editors
(:ctags) or
Emacs-style editors (:etags). If
- no filename is specified, the defaulit tags or
+ no filename is specified, the default tags or
TAGS is
used, respectively. Tags for all the functions, constructors and
types in the currently loaded modules are created. All modules must