Reference
Table of Contents
- Interactive functions
yas-load-snippet-buffer-and-close
(table
&optionalkill
)yas-expand-from-trigger-key
(&optionalfield
)yas-skip-and-clear-or-delete-char
(&optionalfield
)yas-global-mode
(&optionalarg
)yas-recompile-all
()yas-visit-snippet-file
()yas-deactivate-extra-mode
(mode
)yas-prev-field
()yas-load-snippet-buffer
(table
&optionalinteractive
)yas-exit-all-snippets
()yas-next-field
(&optionalarg
)yas-abort-snippet
(&optionalsnippet
)yas-describe-tables
(&optionalwith-nonactive
)yas-expand-from-keymap
()yas-new-snippet
(&optionalno-template
)yas-reload-all
(&optionalno-jit
interactive
)yas-next-field-or-maybe-expand
()yas-activate-extra-mode
(mode
)yas-insert-snippet
(&optionalno-condition
)yas-expand
(&optionalfield
)yas-minor-mode
(&optionalarg
)yas-direct-keymaps-reload
()yas-exit-snippet
(snippet
)yas-about
()yas-minor-mode-on
()yas-skip-and-clear-field
(&optionalfield
)yas-compile-directory
(top-level-dir
)yas-load-directory
(top-level-dir
&optionaluse-jit
interactive
)yas-describe-table-by-namehash
()yas-tryout-snippet
(&optionaldebug
)
- Customization variables
yas-expand-only-for-last-commands
yas-wrap-around-region
yas-new-snippet-default
yas-choose-keys-first
yas-triggers-in-field
yas-use-menu
yas-snippet-dirs
()yas-buffer-local-condition
yas-choose-tables-first
yas-overlay-priority
yas-snippet-revival
yas-good-grace
yas-visit-from-menu
yas-prompt-functions
yas-trigger-symbol
yas-also-indent-empty-lines
yas-also-auto-indent-first-line
yas-indent-line
yas-alias-to-yas/prefix-p
- Useful functions
yas-expand-snippet
(snippet
&optionalstart
end
expand-env
)yas-define-snippets
(mode
snippets
)yas-completing-prompt
(prompt
choices
&optionaldisplay-fn
completion-fn
)yas-inside-string
()yas-lookup-snippet
(name
&optionalmode
noerror
)yas-x-prompt
(prompt
choices
&optionaldisplay-fn
)yas-global-mode-enable-in-buffers
()yas-selected-text
()yas-field-value
(number
)yas-global-mode-cmhh
()yas-escape-text
(text
)yas-dropdown-prompt
(_prompt
choices
&optionaldisplay-fn
)yas-shortest-key-until-whitespace
(_start-point
)yas-substr
(str
pattern
&optionalsubexp
)yas-ido-prompt
(prompt
choices
&optionaldisplay-fn
)yas-maybe-ido-prompt
(prompt
choices
&optionaldisplay-fn
)yas-snippet-mode-buffer-p
()yas-no-prompt
(_prompt
choices
&optional_display-fn
)yas-longest-key-from-whitespace
(start-point
)yas-try-key-from-whitespace
(_start-point
)yas-choose-value
(&restpossibilities
)yas-global-mode-check-buffers
()yas-minor-mode-set-explicitly
()yas-define-menu
(mode
menu
&optionalomit-items
)yas-current-field
()yas-unimplemented
(&optionalmissing-feature
)yas-define-condition-cache
(func
doc
&restbody
)yas-active-keys
()yas-text
()yas-next-field-will-exit-p
(&optionalarg
)yas-active-snippets
(&optionalbeg
end
)yas-verify-value
(possibilities
)yas-default-from-field
(number
)yas-key-to-value
(alist
)yas-throw
(text
)yas-hippie-try-expand
(first-time?
)yas-maybe-load-snippet-buffer
()
- Useful variables
yas-key-syntaxes
yas-modified-p
yas-dont-activate-functions
yas-before-expand-snippet-hook
yas-maybe-skip-and-clear-field
yas-keymap
yas-verbosity
yas-minor-mode-hook
yas-minor-mode-major-mode
yas-not-string-or-comment-condition
yas-after-exit-snippet-hook
yas-maybe-expand
yas-after-reload-hook
yas-new-snippet-buffer-name
yas-snippet-end
yas-minor-mode-map
yas-global-mode-hook
yas-snippet-beg
yas-moving-away-p
yas-maybe-expand-from-keymap
yas-global-mode-buffers
Interactive functions
yas-load-snippet-buffer-and-close
(table
&optional kill
)
Load and save the snippet, then quit-window
if saved.
Loading is performed by yas-load-snippet-buffer
. If the
snippet is new, ask the user whether (and where) to save it. If
the snippet already has a file, just save it.
The prefix argument kill
is passed to quit-window
.
Don't use this from a Lisp program, call yas-load-snippet-buffer
and kill-buffer
instead.
yas-expand-from-trigger-key
(&optional field
)
Expand a snippet before point.
If no snippet expansion is possible, fall back to the behaviour
defined in yas-fallback-behavior
.
Optional argument field
is for non-interactive use and is an
object satisfying yas--field-p
to restrict the expansion to.
yas-skip-and-clear-or-delete-char
(&optional field
)
Clears unmodified field if at field start, skips to next tab.
Otherwise deletes a character normally by calling delete-char
.
yas-global-mode
(&optional arg
)
Toggle Yas minor mode in all buffers.
With prefix arg
, enable Yas-Global mode if arg
is positive;
otherwise, disable it. If called from Lisp, enable the mode if
arg
is omitted or nil.
Yas minor mode is enabled in all buffers where
yas-minor-mode-on
would do it.
See yas-minor-mode
for more information on Yas minor mode.
yas-recompile-all
()
Compile every dir in yas-snippet-dirs
.
yas-visit-snippet-file
()
Choose a snippet to edit, selection like yas-insert-snippet
.
Only success if selected snippet was loaded from a file. Put the
visited file in snippet-mode
.
yas-load-snippet-buffer
(table
&optional interactive
)
Parse and load current buffer's snippet definition into table
.
table
is a symbol name passed to yas--table-get-create
. When
called interactively, prompt for the table name.
Return the yas--template
object created
yas-expand-from-keymap
()
Expand/run snippets from keymaps, possibly falling back to original binding.
yas-new-snippet
(&optional no-template
)
Pops a new buffer for writing a snippet.
Expands a snippet-writing snippet, unless the optional prefix arg
no-template
is non-nil.
yas-reload-all
(&optional no-jit
interactive
)
Reload all snippets and rebuild the YASnippet menu.
When no-jit
is non-nil force immediate reload of all known
snippets under yas-snippet-dirs
, otherwise use just-in-time
loading.
When called interactively, use just-in-time loading when given a prefix argument.
yas-next-field-or-maybe-expand
()
Try to expand a snippet at a key before point.
Otherwise delegate to yas-next-field
.
yas-activate-extra-mode
(mode
)
Activates the snippets for the given mode
in the buffer.
The function can be called in the hook of a minor mode to activate snippets associated with that mode.
yas-insert-snippet
(&optional no-condition
)
Choose a snippet to expand, pop-up a list of choices according
to yas-prompt-functions
.
With prefix argument no-condition
, bypass filtering of snippets
by condition.
yas-expand
(&optional field
)
Expand a snippet before point. If no snippet
expansion is possible, defer to yas-fallback-behavior
(which see).
Optional argument field
is for non-interactive use and is an
object satisfying yas--field-p
to restrict the expansion to.
yas-minor-mode
(&optional arg
)
Toggle YASnippet mode.
When YASnippet mode is enabled, yas-expand
, normally bound to
the tab key, expands snippets of code depending on the major
mode.
With no argument, this command toggles the mode. positive prefix argument turns on the mode. Negative prefix argument turns off the mode.
Key bindings:
key binding --- ------- C-c Prefix Command C-c & Prefix Command C-c & C-n yas-new-snippet C-c & C-s yas-insert-snippet C-c & C-v yas-visit-snippet-file
yas-minor-mode-on
()
Turn on YASnippet minor mode.
Honour yas-dont-activate-functions
, which see.
yas-skip-and-clear-field
(&optional field
)
Clears unmodified field
if at field start, skips to next tab.
yas-compile-directory
(top-level-dir
)
Create .yas-compiled-snippets.el files under subdirs of top-level-dir
.
This works by stubbing a few functions, then calling
yas-load-directory
.
Customization variables
yas-expand-only-for-last-commands
List of last-command
values to restrict tab-triggering to, or nil.
Leave this set at nil (the default) to be able to trigger an expansion simply by placing the cursor after a valid tab trigger, using whichever commands.
Optionally, set this to something like (self-insert-command) if you to wish restrict expansion to only happen when the last letter of the snippet tab trigger was typed immediately before the trigger key itself.
yas-wrap-around-region
What to insert for snippet's $0 field.
If set to a character, insert contents of corresponding register.
If non-nil insert region contents. This can be overridden on a
per-snippet basis. A value of cua
is considered equivalent to
`?0' for backwards compatibility.
yas-new-snippet-default
Default snippet to use when creating a new snippet. If nil, don't use any snippet.
yas-choose-keys-first
If non-nil, prompt for snippet key first, then for template.
Otherwise prompts for all possible snippet names.
This affects yas-insert-snippet
and yas-visit-snippet-file
.
yas-triggers-in-field
If non-nil, allow stacked expansions (snippets inside snippets).
Otherwise yas-next-field-or-maybe-expand
just moves on to the
next field
yas-snippet-dirs
()
Return variable yas-snippet-dirs
as list of strings.
yas-buffer-local-condition
Snippet expanding condition.
This variable is a Lisp form which is evaluated every time a snippet expansion is attempted:
- If it evaluates to nil, no snippets can be expanded.
- If it evaluates to the a cons (require-snippet-condition
. requirement)
- Snippets bearing no "# condition:" directive are not considered
- Snippets bearing conditions that evaluate to nil (or produce an error) won't be considered.
- If the snippet has a condition that evaluates to non-nil
result:
- If requirement is t, the snippet is considered
- If requirement is
eq
result, the snippet is considered - Otherwise, the snippet is not considered.
- If it evaluates to the symbol
always
, all snippets are considered for expansion, regardless of any conditions. - If it evaluates to t or some other non-nil value
- Snippet bearing no conditions, or conditions that evaluate to non-nil, are considered for expansion.
- Otherwise, the snippet is not considered.
Here's an example preventing snippets from being expanded from
inside comments, in python-mode
only, with the exception of
snippets returning the symbol force-in-comment
in their
conditions.
(add-hook 'python-mode-hook (lambda () (setq yas-buffer-local-condition '(if (python-syntax-comment-or-string-p) '(require-snippet-condition . force-in-comment) t))))
yas-choose-tables-first
If non-nil, and multiple eligible snippet tables, prompts user for tables first.
Otherwise, user chooses between the merging together of all eligible tables.
This affects yas-insert-snippet
, yas-visit-snippet-file
yas-overlay-priority
Priority to use for yasnippets overlays.
This is useful to control whether snippet navigation bindings
override bindings from other packages (e.g., company-mode
).
yas-good-grace
If non-nil, don't raise errors in elisp evaluation.
This affects both the inline elisp in snippets and the hook
variables such as yas-after-exit-snippet-hook
.
If this variable's value is inline
, an error string "[yas]
error" is returned instead of raising the error. If this
variable's value is hooks
, a message is output to according to
yas-verbosity-level
. If this variable's value is t, both are
active.
yas-prompt-functions
Functions to prompt for keys, templates, etc interactively.
These functions are called with the following arguments:
- prompt: A string to prompt the user
- choices: a list of strings or objects.
- optional display-fn : A function that, when applied to each of
the objects in choices will return a string.
The return value of any function you put here should be one of the objects in choices, properly formatted with display-fn (if that is passed).
- To signal that your particular style of prompting is
unavailable at the moment, you can also have the function return nil.
- To signal that the user quit the prompting process, you can
signal quit
with
(signal 'quit "user quit!")
yas-also-auto-indent-first-line
Non-nil means also auto indent first line according to mode.
Naturally this is only valid when yas-indent-line
is auto
.
yas-indent-line
Controls indenting applied to a recent snippet expansion.
The following values are possible:
fixed
Indent the snippet to the current column;auto
Indent each line of the snippet withindent-according-to-mode
Every other value means don't apply any snippet-side indentation after expansion (the manual per-line "$>" indentation still applies).
Useful functions
yas-expand-snippet
(snippet
&optional start
end
expand-env
)
Expand snippet
at current point.
Text between start
and end
will be deleted before inserting
template. expand-env
is a list of (sym value) let-style dynamic
bindings considered when expanding the snippet. If omitted, use
snippet
's expand-env field.
snippet
may be a snippet structure (e.g., as returned by
yas-lookup-snippet
), or just a snippet body (which is a string
for normal snippets, and a list for command snippets).
yas-define-snippets
(mode
snippets
)
Define snippets
for mode
.
snippets
is a list of snippet definitions, each taking the
following form
(key template name condition group expand-env load-file keybinding uuid save-file)
Within these, only key and template are actually mandatory.
template might be a Lisp form or a string, depending on whether this is a snippet or a snippet-command.
condition, expand-env and keybinding are Lisp forms, they have
been yas--read-lisp
-ed and will eventually be
yas--eval-for-string
-ed.
The remaining elements are strings.
file is probably of very little use if you're programatically defining snippets.
uuid is the snippet's "unique-id". Loading a second snippet file with the same uuid would replace the previous snippet.
You can use yas--parse-template
to return such lists based on
the current buffers contents.
yas-completing-prompt
(prompt
choices
&optional display-fn
completion-fn
)
warning: no doc for symbol yas-completing-prompt
yas-lookup-snippet
(name
&optional mode
noerror
)
Get the snippet named name
in mode
's tables.
mode
defaults to the current buffer's major-mode
. If noerror
is non-nil, then don't signal an error if there isn't any snippet
called name
.
Honours yas-buffer-local-condition
.
yas-selected-text
()
Return yas-selected-text
if that exists and is non-empty, else nil.
yas-field-value
(number
)
Get the string for field with number
.
Use this in primary and mirror transformations to get the text of other fields.
yas-dropdown-prompt
(_prompt
choices
&optional display-fn
)
warning: no doc for symbol yas-dropdown-prompt
yas-shortest-key-until-whitespace
(_start-point
)
Like yas-longest-key-from-whitespace
but take the shortest key.
yas-substr
(str
pattern
&optional subexp
)
Search pattern
in str
and return subexp
th match.
If found, the content of subexp group subexp
(default 0) is
returned, or else the original str
will be returned.
yas-maybe-ido-prompt
(prompt
choices
&optional display-fn
)
warning: no doc for symbol yas-maybe-ido-prompt
yas-snippet-mode-buffer-p
()
Return non-nil if current buffer should be in snippet-mode
.
Meaning it's visiting a file under one of the mode directories in
yas-snippet-dirs
.
yas-longest-key-from-whitespace
(start-point
)
As yas-key-syntaxes
element, look for longest key between point and whitespace.
A newline will be considered whitespace even if the mode syntax marks it as something else (typically comment ender).
yas-try-key-from-whitespace
(_start-point
)
As yas-key-syntaxes
element, look for whitespace delimited key.
A newline will be considered whitespace even if the mode syntax marks it as something else (typically comment ender).
yas-choose-value
(&rest possibilities
)
Prompt for a string in possibilities
and return it.
The last element of possibilities
may be a list of strings.
yas-define-condition-cache
(func
doc
&rest body
)
Define a function func
with doc doc
and body body
.
body
is executed at most once every snippet expansion attempt, to check
expansion conditions.
It doesn't make any sense to call func
programatically.
yas-text
()
Return yas-text
if that exists and is non-empty, else nil.
yas-next-field-will-exit-p
(&optional arg
)
Return non-nil if (yas-next-field arg
) would exit the current snippet.
yas-active-snippets
(&optional beg
end
)
Return a sorted list of active snippets. The most recently-inserted snippets are returned first.
Only snippets overlapping the region beg
… end
are returned.
Overlapping has the same meaning as described in overlays-in
.
If end
is omitted, it defaults to (1+ beg
). If beg
is omitted,
it defaults to point. A non-nil, non-buffer position beg
is
equivalent to a range covering the whole buffer.
yas-verify-value
(possibilities
)
Verify that the current field value is in possibilities
.
Otherwise signal yas-exception
.
Useful variables
yas-key-syntaxes
Syntaxes and functions to help look for trigger keys before point.
Each element in this list specifies how to skip buffer positions backwards and look for the start of a trigger key.
Each element can be either a string or a function receiving the
original point as an argument. A string element is simply passed
to skip-syntax-backward
whereas a function element is called
with no arguments and should also place point before the original
position.
The string between the resulting buffer position and the original point is matched against the trigger keys in the active snippet tables.
If no expandable snippets are found, the next element is the list
is tried, unless a function element returned the symbol again
,
in which case it is called again from the previous position and
may once more reposition point.
For example, if yas-key-syntaxes
has the value ("w" "w_"),
trigger keys composed exclusively of "word"-syntax characters
are looked for first. Failing that, longer keys composed of
"word" or "symbol" syntax are looked for. Therefore,
triggering after
foo-bar
will, according to the "w" element first try "barbaz". If
that isn't a trigger key, "foo-barbaz" is tried, respecting the
second "w_" element. Notice that even if "baz" is a trigger
key for an active snippet, it won't be expanded, unless a
function is added to yas-key-syntaxes
that eventually places
point between "bar" and "baz".
See also Info node (elisp) Syntax Descriptors.
yas-dont-activate-functions
Special hook to control which buffers yas-global-mode
affects.
Functions are called with no argument, and should return non-nil to prevent
yas-global-mode
from enabling yasnippet in this buffer.
In Emacsen < 24, this variable is buffer-local. Because
yas-minor-mode-on
is called by yas-global-mode
after
executing the buffer's major mode hook, setting this variable
there is an effective way to define exceptions to the "global"
activation behaviour.
In Emacsen >= 24, only the global value is used. To define
per-mode exceptions to the "global" activation behaviour, call
yas-minor-mode
with a negative argument directily in the major
mode's hook.
yas-maybe-skip-and-clear-field
A conditional key definition.
This can be used as a key definition in keymaps to bind a key to
yas-skip-and-clear-field
only when at the beginning of an
unmodified snippey field.
yas-minor-mode-hook
Hook run when yas-minor-mode
is turned on.
yas-not-string-or-comment-condition
Disables snippet expansion in strings and comments.
To use, set yas-buffer-local-condition
to this value.
yas-after-exit-snippet-hook
Hooks to run after a snippet exited.
The hooks will be run in an environment where some variables bound to proper values:
yas-snippet-beg
: The beginning of the region of the snippet.
yas-snippet-end
: Similar to beg.
Attention: These hooks are not run when exiting nested/stacked snippet expansion!
yas-maybe-expand
A conditional key definition.
This can be used as a key definition in keymaps to bind a key to
yas-expand
only when there is a snippet available to be
expanded.
yas-after-reload-hook
Hooks run after yas-reload-all
.
yas-minor-mode-map
The keymap used when yas-minor-mode
is active.
yas-global-mode-hook
Hook run after entering or leaving yas-global-mode
.
No problems result if this variable is not bound.
add-hook
automatically binds it. (This is true for all hook variables.)