History
- The history file
- Loading history
- Saving history
- The hist command (overview)
- The
grepoption - The
tailoption - The
headoption - The
no-numbersoption - The
replayoption - The
excludeoption - The
saveoption - The
showoption - The
clearoption
The ability to control history is a useful feature in itself, but it becomes indispensable when your REPL sessions become large or complicated. As a result, Pry provides rich history management, enabling you to load, save, view, and replay history, among other things.
As stated in the customization section
the Pry.config.history_file option can be used to set the history
file - the file where history is saved to and loaded from.
Note that because both the .pryrc file and plugins are loaded before the history file, you can change the history options in either of these places. You can also change it any point before you start Pry when invoking it at runtime.
The default history file is ~/.pry_history or ~/.local/share/pry/pry_history
Example: Use irb's history file instead
Pry.config.history_file = "~/.irb_history"The Pry.config.history_load option determines whether history
will be loaded from the history file when
a Pry session starts. This option can be modified in any of the places
given in the history file section,
above.
Loading history will pre-populate the Readline::HISTORY array with
the content in the history file.
The default value is true
Example: Disable history loading
Pry.config.history_load = falseThe Pry.config.history_save option determines whether history
will be saved to the history file when
a Pry session ends. This option can be modified in any of the places
given in the history file section,
above.
The default value is true
Example: Disable history saving
Pry.config.history_save = falseThe hist command is the primary interface to your Pry history. The
hist command enables you to view, search, and
replay history, among other things.
Note however that the current version of the hist command does not
allow options to stack; that is hist --tail 10 --grep hello does not
perform as expected. This feature will be added in a future version.
The hist command when invoked by itself with no options will simply
display all Pry history. If there is more than a screenful of history
the output will be sent through a pager.
Example: Display all Pry history
pry(main)> hist
0: require 'bacon'
1: $ describe
2: ? describe
3: ls -M Bacon::Context
4: hist
When the --grep REGEX option is passed to hist only those lines
which match the regular expression will be displayed.
pry(main)> hist --grep desc
1: $ describe
2: ? describe
When the --tail N option is passed to hist only the last N lines
of history will be displayed. Note that if the N parameter is left
out then hist will default to displaying the last 10 lines.
Example:
pry(main) hist --tail 5
12: puts "silk banners, drove of pure lilies"
13: puts "beneath walls a virgin once defended;"
14: end
14: end
15: hist --tail 5
When the --head N option is passed to hist only the first N lines
of history will be displayed. Note that if the N parameter is left
out then hist will default to displaying the first 10 lines.
Example:
pry(main)> hist --head 3
0: require 'bacon'
1: $ describe
2: ? describe
The --no-numbers (or -n) switch turns off line numbers when displaying readline history. This can be
useful as an alternative to --replay as it enables easy copy/pasting of history back into Pry for replaying.
[8] (pry) main: 0> hist -n -T
hist -n
hist -T -n
.clear
hist -n -T
def hello
puts "hi"
end
(1..3).each do |v|
puts v * 6
end
[9] (pry) main: 0>
The --replay A..B option allows us to replay lines of history. It
accepts either a single line number or a range of numbers. It even
allows replaying of incomplete multi line expressions.
Example:
pry(main)> hist --tail 3
7000: puts "hello world";
7001: puts "good evening world";
7002: hist --tail 3
pry(main)> hist --replay 7000
hello world
Example: Replaying an incomplete multi-line expression
pry(main)> hist --tail 6
7008: class Evening
7009: def sundown
7010: puts "goodnight"
7011: end
7012: end
7013: hist --tail 6
pry(main)> hist --replay 7008..7011
pry(main)* def moonout
pry(main)* puts "dog's bark"
pry(main)* end
pry(main)* end;
pry(main)> Evening.new.moonout;
dog's bark
pry(main)>
The --exclude-pry option, or -e, displays all lines of history except those that
are Pry commands.
Example: Comparision of hist with and without --exclude-pry
pry(main)> hist
0: hist
1: ls -m
2: show-method Gem.ruby
3: hist
4: puts "testing: 1, 2, 3..."
5: 1 + 3
6: hist
pry(main)> hist --exclude-pry
4: puts "testing: 1, 2, 3..."
5: 1 + 3
pry(main)>
The --save [A..B] FILE option allows you to save lines from the
history buffer to a file. If the range is left out the entire history is
saved to the specified file. Note that an implied --exclude is
performed on the lines before saving -- only valid Ruby code is saved.
Example:
pry(main)> hist
0: hist
1: ls -m
2: show-method Gem.ruby
3: hist
4: puts "testing: 1, 2, 3..."
5: 1 + 3
6: hist
7: hist --exclude
8: hist -h
9: hist
pry(main)> hist --save 4..5 test.rb
Saving history in /Users/john/ruby/projects/pry.wiki/test.rb ...
... history saved.
pry(main)> cat test.rb
puts "testing: 1, 2, 3..."
1 + 3
pry(main)>
The --show A..B options displays the line or range of lines to the
user. May be useful when used after the --grep option and before the
--replay option.
Example:
pry(main)> hist --show 2..5
2: show-method Gem.ruby
3: hist
4: puts "testing: 1, 2, 3..."
5: 1 + 3
pry(main)>
The --clear option clears all current session history.
Example:
pry(main)> hist --clear
History cleared.
pry(main)> hist
0: hist
pry(main)>