mirror of
https://github.com/QB64Official/qb64.git
synced 2024-09-03 06:50:15 +00:00
335 lines
7.7 KiB
Tcl
335 lines
7.7 KiB
Tcl
# history.tcl --
|
||
#
|
||
# Implementation of the history command.
|
||
#
|
||
# Copyright (c) 1997 Sun Microsystems, Inc.
|
||
#
|
||
# See the file "license.terms" for information on usage and redistribution of
|
||
# this file, and for a DISCLAIMER OF ALL WARRANTIES.
|
||
#
|
||
|
||
# The tcl::history array holds the history list and some additional
|
||
# bookkeeping variables.
|
||
#
|
||
# nextid the index used for the next history list item.
|
||
# keep the max size of the history list
|
||
# oldest the index of the oldest item in the history.
|
||
|
||
namespace eval ::tcl {
|
||
variable history
|
||
if {![info exists history]} {
|
||
array set history {
|
||
nextid 0
|
||
keep 20
|
||
oldest -20
|
||
}
|
||
}
|
||
|
||
namespace ensemble create -command ::tcl::history -map {
|
||
add ::tcl::HistAdd
|
||
change ::tcl::HistChange
|
||
clear ::tcl::HistClear
|
||
event ::tcl::HistEvent
|
||
info ::tcl::HistInfo
|
||
keep ::tcl::HistKeep
|
||
nextid ::tcl::HistNextID
|
||
redo ::tcl::HistRedo
|
||
}
|
||
}
|
||
|
||
# history --
|
||
#
|
||
# This is the main history command. See the man page for its interface.
|
||
# This does some argument checking and calls the helper ensemble in the
|
||
# tcl namespace.
|
||
|
||
proc ::history {args} {
|
||
# If no command given, we're doing 'history info'. Can't be done with an
|
||
# ensemble unknown handler, as those don't fire when no subcommand is
|
||
# given at all.
|
||
|
||
if {![llength $args]} {
|
||
set args info
|
||
}
|
||
|
||
# Tricky stuff needed to make stack and errors come out right!
|
||
tailcall apply {arglist {tailcall history {*}$arglist} ::tcl} $args
|
||
}
|
||
|
||
# (unnamed) --
|
||
#
|
||
# Callback when [::history] is destroyed. Destroys the implementation.
|
||
#
|
||
# Parameters:
|
||
# oldName what the command was called.
|
||
# newName what the command is now called (an empty string).
|
||
# op the operation (= delete).
|
||
#
|
||
# Results:
|
||
# none
|
||
#
|
||
# Side Effects:
|
||
# The implementation of the [::history] command ceases to exist.
|
||
|
||
trace add command ::history delete [list apply {{oldName newName op} {
|
||
variable history
|
||
unset -nocomplain history
|
||
foreach c [info procs ::tcl::Hist*] {
|
||
rename $c {}
|
||
}
|
||
rename ::tcl::history {}
|
||
} ::tcl}]
|
||
|
||
# tcl::HistAdd --
|
||
#
|
||
# Add an item to the history, and optionally eval it at the global scope
|
||
#
|
||
# Parameters:
|
||
# event the command to add
|
||
# exec (optional) a substring of "exec" causes the command to
|
||
# be evaled.
|
||
# Results:
|
||
# If executing, then the results of the command are returned
|
||
#
|
||
# Side Effects:
|
||
# Adds to the history list
|
||
|
||
proc ::tcl::HistAdd {event {exec {}}} {
|
||
variable history
|
||
|
||
if {
|
||
[prefix longest {exec {}} $exec] eq ""
|
||
&& [llength [info level 0]] == 3
|
||
} then {
|
||
return -code error "bad argument \"$exec\": should be \"exec\""
|
||
}
|
||
|
||
# Do not add empty commands to the history
|
||
if {[string trim $event] eq ""} {
|
||
return ""
|
||
}
|
||
|
||
# Maintain the history
|
||
set history([incr history(nextid)]) $event
|
||
unset -nocomplain history([incr history(oldest)])
|
||
|
||
# Only execute if 'exec' (or non-empty prefix of it) given
|
||
if {$exec eq ""} {
|
||
return ""
|
||
}
|
||
tailcall eval $event
|
||
}
|
||
|
||
# tcl::HistKeep --
|
||
#
|
||
# Set or query the limit on the length of the history list
|
||
#
|
||
# Parameters:
|
||
# limit (optional) the length of the history list
|
||
#
|
||
# Results:
|
||
# If no limit is specified, the current limit is returned
|
||
#
|
||
# Side Effects:
|
||
# Updates history(keep) if a limit is specified
|
||
|
||
proc ::tcl::HistKeep {{count {}}} {
|
||
variable history
|
||
if {[llength [info level 0]] == 1} {
|
||
return $history(keep)
|
||
}
|
||
if {![string is integer -strict $count] || ($count < 0)} {
|
||
return -code error "illegal keep count \"$count\""
|
||
}
|
||
set oldold $history(oldest)
|
||
set history(oldest) [expr {$history(nextid) - $count}]
|
||
for {} {$oldold <= $history(oldest)} {incr oldold} {
|
||
unset -nocomplain history($oldold)
|
||
}
|
||
set history(keep) $count
|
||
}
|
||
|
||
# tcl::HistClear --
|
||
#
|
||
# Erase the history list
|
||
#
|
||
# Parameters:
|
||
# none
|
||
#
|
||
# Results:
|
||
# none
|
||
#
|
||
# Side Effects:
|
||
# Resets the history array, except for the keep limit
|
||
|
||
proc ::tcl::HistClear {} {
|
||
variable history
|
||
set keep $history(keep)
|
||
unset history
|
||
array set history [list \
|
||
nextid 0 \
|
||
keep $keep \
|
||
oldest -$keep \
|
||
]
|
||
}
|
||
|
||
# tcl::HistInfo --
|
||
#
|
||
# Return a pretty-printed version of the history list
|
||
#
|
||
# Parameters:
|
||
# num (optional) the length of the history list to return
|
||
#
|
||
# Results:
|
||
# A formatted history list
|
||
|
||
proc ::tcl::HistInfo {{count {}}} {
|
||
variable history
|
||
if {[llength [info level 0]] == 1} {
|
||
set count [expr {$history(keep) + 1}]
|
||
} elseif {![string is integer -strict $count]} {
|
||
return -code error "bad integer \"$count\""
|
||
}
|
||
set result {}
|
||
set newline ""
|
||
for {set i [expr {$history(nextid) - $count + 1}]} \
|
||
{$i <= $history(nextid)} {incr i} {
|
||
if {![info exists history($i)]} {
|
||
continue
|
||
}
|
||
set cmd [string map [list \n \n\t] [string trimright $history($i) \ \n]]
|
||
append result $newline[format "%6d %s" $i $cmd]
|
||
set newline \n
|
||
}
|
||
return $result
|
||
}
|
||
|
||
# tcl::HistRedo --
|
||
#
|
||
# Fetch the previous or specified event, execute it, and then replace
|
||
# the current history item with that event.
|
||
#
|
||
# Parameters:
|
||
# event (optional) index of history item to redo. Defaults to -1,
|
||
# which means the previous event.
|
||
#
|
||
# Results:
|
||
# Those of the command being redone.
|
||
#
|
||
# Side Effects:
|
||
# Replaces the current history list item with the one being redone.
|
||
|
||
proc ::tcl::HistRedo {{event -1}} {
|
||
variable history
|
||
|
||
set i [HistIndex $event]
|
||
if {$i == $history(nextid)} {
|
||
return -code error "cannot redo the current event"
|
||
}
|
||
set cmd $history($i)
|
||
HistChange $cmd 0
|
||
tailcall eval $cmd
|
||
}
|
||
|
||
# tcl::HistIndex --
|
||
#
|
||
# Map from an event specifier to an index in the history list.
|
||
#
|
||
# Parameters:
|
||
# event index of history item to redo.
|
||
# If this is a positive number, it is used directly.
|
||
# If it is a negative number, then it counts back to a previous
|
||
# event, where -1 is the most recent event.
|
||
# A string can be matched, either by being the prefix of a
|
||
# command or by matching a command with string match.
|
||
#
|
||
# Results:
|
||
# The index into history, or an error if the index didn't match.
|
||
|
||
proc ::tcl::HistIndex {event} {
|
||
variable history
|
||
if {![string is integer -strict $event]} {
|
||
for {set i [expr {$history(nextid)-1}]} {[info exists history($i)]} \
|
||
{incr i -1} {
|
||
if {[string match $event* $history($i)]} {
|
||
return $i
|
||
}
|
||
if {[string match $event $history($i)]} {
|
||
return $i
|
||
}
|
||
}
|
||
return -code error "no event matches \"$event\""
|
||
} elseif {$event <= 0} {
|
||
set i [expr {$history(nextid) + $event}]
|
||
} else {
|
||
set i $event
|
||
}
|
||
if {$i <= $history(oldest)} {
|
||
return -code error "event \"$event\" is too far in the past"
|
||
}
|
||
if {$i > $history(nextid)} {
|
||
return -code error "event \"$event\" hasn't occured yet"
|
||
}
|
||
return $i
|
||
}
|
||
|
||
# tcl::HistEvent --
|
||
#
|
||
# Map from an event specifier to the value in the history list.
|
||
#
|
||
# Parameters:
|
||
# event index of history item to redo. See index for a description of
|
||
# possible event patterns.
|
||
#
|
||
# Results:
|
||
# The value from the history list.
|
||
|
||
proc ::tcl::HistEvent {{event -1}} {
|
||
variable history
|
||
set i [HistIndex $event]
|
||
if {![info exists history($i)]} {
|
||
return ""
|
||
}
|
||
return [string trimright $history($i) \ \n]
|
||
}
|
||
|
||
# tcl::HistChange --
|
||
#
|
||
# Replace a value in the history list.
|
||
#
|
||
# Parameters:
|
||
# newValue The new value to put into the history list.
|
||
# event (optional) index of history item to redo. See index for a
|
||
# description of possible event patterns. This defaults to 0,
|
||
# which specifies the current event.
|
||
#
|
||
# Side Effects:
|
||
# Changes the history list.
|
||
|
||
proc ::tcl::HistChange {newValue {event 0}} {
|
||
variable history
|
||
set i [HistIndex $event]
|
||
set history($i) $newValue
|
||
}
|
||
|
||
# tcl::HistNextID --
|
||
#
|
||
# Returns the number of the next history event.
|
||
#
|
||
# Parameters:
|
||
# None.
|
||
#
|
||
# Side Effects:
|
||
# None.
|
||
|
||
proc ::tcl::HistNextID {} {
|
||
variable history
|
||
return [expr {$history(nextid) + 1}]
|
||
}
|
||
|
||
return
|
||
|
||
# Local Variables:
|
||
# mode: tcl
|
||
# fill-column: 78
|
||
# End:
|