Conditional Logic

If you want to have your Bunches perform different tasks based on various criteria, conditional logic can add flexibility and control.

• Syntax
  • Boolean Operators
  • Nesting If/Else Blocks
  • Waiting Snippets in If/Else Blocks
• Conditions
• Tips
  • Use Script Results As Conditions
  • Combine Dialogs and Conditions
  • Use Snippets To Run Conditional Logic On Close

Syntax

Bunch supports if/else syntax. There are a number of conditions you can use to determine if a certain block will run. The most basic form of this is the “if” statement. The block starts with an “if condition” line, no indentation, and ends with a line containing just “end”. The contents between the “if” and “end” are indented 4 spaces or one tab.

if var_one
	Messages
	<Snippets.snip#Group 1
end

Indentation must be exactly four (4) spaces or one (1) tab per level, with an additional 4 spaces/1 tab per nested level. If using spaces instead of tabs, every indentation level must be a multiple of 4.

The condition can use a variety of syntax, from human readable to symbolic. See the next section for details. In the example above, Bunch simply tests the contents of a variable called var_one to see if it exists (is defined and has a value that’s not “false” or “no”). If so, it launches Messages and runs a snippet.

You can go further by providing “else” statements. These can be “else if condition”, or just “else” to have a block that runs if nothing else matches. Both are optional. If used, the “else” block should come last.

if var_one is "Choice 1"
	var_two = "Project 1"
	<<#Load Project
else if var_one is "Choice 2"
	var_two = "Project 2"
	<<#Load Project
else
	<<#Load Default
end

Boolean Operators

Conditions can be combined using “AND” and “OR”.

if condition 1 AND condition 2
	<<#You Win
end

You can group multiple conditions in parentheses and compare multiple groupings.

if (condition 1 AND condition 2) OR (condition 3 AND condition 4)
	<<#You Win
end

Nesting If/Else Blocks

You can nest if/else blocks, continuing to indent contents 4 spaces or one tab from the last level of indentation. Variables can be changed within blocks and tested again in nested conditions.

test_var = true

if test_var
	(log test_var is true)
	test_var = false

	if test_var
		(log test_var is true)
	else
		(log test_var is false)
	end
end

Waiting Snippets in If/Else Blocks

Waiting Snippets are specified by indenting 4 spaces or 1 tab, so within an if/else block they should be indented an extra 4 spaces or 1 tab beyond the indentation of the block level.

if TweetBot is running
	Messages
		<<#Position Comms
end

Conditions

Variable names in conditions can be “bare,” writing just the variable name. You can optionally use a $, e.g. $variable for clarity. If a variable matching the key isn’t defined, it will return false and not run the block. If your variable name contains spaces, you must either write it without spaces (first name -> firstname) or use curly brackets (${first name}).

All conditions can be negated using “not” or ! condition. Negatives can only be invoked once, e.g. weekday not !Friday will be interpreted as weekday is not Friday.

Syntax: if [condition] where [condition] is one of the following.

UUID

Test if the current machine UUID matches

uuid is C6766848-065C-51F8-B2EE-3A9DA8A10017	UUID matches
uuid is not C6766848-065C-51F8-B2EE-3A9DA8A10017	UUID does not match
C6766848-065C-51F8-B2EE-3A9DA8A10017	UUID matches
not C6766848-065C-51F8-B2EE-3A9DA8A10017	UUID does not match

File exists/contains

Test if a given file path exists, and optionally if it contains a text string

file PATH exists	File exists at path
file PATH does not exist	File does not exist at path
file PATH	File exists
!file PATH	File does not exist
file PATH contains TEXT	File at PATH exists and contains the text TEXT
file PATH does not contain TEXT	File at PATH either doesn’t exist, or doesn’t contain text

Bunch Phase

Test if a Bunch is in the process of opening or closing (phase). Use “self” or “this” to test current Bunch.

self is opening	Current Bunch is opening
self is closing	Current Bunch is closing
BunchName is opening	Test another Bunch such as a parent Bunch which opened this Bunch

Bunch State

Test if another Bunch is currently open or closed.

BunchName is open	Bunch is currently open
BunchName is closed	Bunch is currently closed. Also works as BunchName is not open

Parent

If a Bunch was opened by another Bunch, its parent can be tested

has parent/is child	Bunch was opened by another Bunch
not parent/is not child	Negative test
!child	Negative shorthand
parent is BunchName	Test which Bunch opened this Bunch Any text comparison operators work e.g. parent contains PartialName

App is running

Test if a given app is running or not.

Example: if Messages is running

AppName is running	App is currently running
AppName is not running	App is not running

is is optional in all tests, so this works as AppName running, AppName not running

Numeric

Test a variable’s contents numerically. Conditions can be written out or represented with mathematical symbols.

All conditions can be negated with not, e.g. var_name is not less than is the same as var_name is greater than or equal to. Symbols can be negated with !, e.g. var_name !<= 5.

Example: if var_name is greater than 1

Natural language	Symbolic
is less than	var_name < 5
is less than or equal	var_name <= 5
is greater than	var_name > 1
is greater than or equal to	var_name >= 3
equals / is equal / is	var_name == 2

Text

Compare variable contents as a string. Comparisons are always case insensitive.

Example: if var_name contains "complete"

Natural language	Symbolic
is / is not	== / !=
starts with / does not start with	^= / !^=
ends with / does not end with	$= / !$=
contains / does not contain	*= / !*=

“Truthy”

If the string being compared to is “yes”, “no”, “true”, or “false”, the comparison is “truthy”, meaning it’s registered as a boolean (true/false), and if the variable starts with “t”, “y”, or a number greater than 0, it matches true, and if it starts with “n”, “f”, or zero, it matches false.

I.e. if var_name is set to “yes” and the condition is if var_name is true, the condition will pass.

You can also test if a variable was left empty (e.g. by cancelling a dialog that would set it) using if not variable, which will return true if the variable was not set.

Weekday

Test whether the current weekday is before, after or is a given day, with the week starting on Sunday. Days can be abbreviated with standard abbreviations (mon, wed, fri). This comparison only works in English. The condition just needs to start with weekday.

Remember that you can combine multiple conditions with “OR”, so to have a block run on Tuesday and Thursday, use weekday is Tues OR weekday is Thurs

Example: if weekday is Wednesday

weekday is / is not	Current weekday matches
weekday is before / is not before	From Sunday up to current day
weekday is after / is not after	After current day and before next Sunday

Time

Test whether the current time is before, after, or matches a test value. Times can be in 24-hour format, or 12-hour with a meridian (am/pm).

Example: if time is before 12pm

time is / is not	Current time matches
time is before / is not before	Between 12am and current time
time is after / is not after	Between current time and 12am

Tips

Use Script Results As Conditions

You can use the output of shell scripts to set variables which can then be tested with if/else blocks.

my_var = $ test_script.sh // returns a string value on STDOUT

if my_var is "result one"
	<<#First Result
else if my_var is "result two"
	<<#Second Result
end

This works with AppleScripts as well (my_var = * ...), as long as the script returns a string or number.

There are a some UNIX commands commands that can make very useful variables with things like your clipboard contents or various date formats.

Combine Dialogs and Conditions

You can set a variable using a dialog, and then use an if/else block to perform different actions based on the choice. In its simplest form, this is essentially the same as just having a dialog run different snippets based on user selection, but by setting a variable you can have multiple if/else blocks, and the variable is passed to snippets (which can also contain their own if/else blocks).

my_var = ?[Option 1, Option 2, Option 3] "Which option?"

if !my_var // dialog was cancelled
	(notify Cancelled)
else if my_var ends with "1"
	Sublime Text
	- ~/Code/My Project
	my_var_2 = $ Test.sh // set a second variable
	// both my_var and my_var_2 are passed to any snippets called
	// which can then branch further
	<<#First
else if my_var ends with "2"
	...
end

Use Snippets To Run Conditional Logic On Close

Because if/else blocks can be used within Snippets, you can use an on-close Snippet to run logic when closing a Bunch.

!<<#On Close
__________________________
-[On Close]---------------
if Tweetbot is not running
	Comms.bunch
end