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Conditional Logic

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

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.

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.
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 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