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expression [2014/07/23 07:49]
l [Summary of types of data values]
expression [2017/10/09 20:39] (current)
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 +<- [[display|Displaying A Passage Within Another]] --------- [[function|About Functions]]->​
 +
 ===== About Expressions ===== ===== About Expressions =====
  
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 | ''​%'' ​   | Modulo (remainder of a division). | ''​5 % 26''​ (is 1) | | ''​%'' ​   | Modulo (remainder of a division). | ''​5 % 26''​ (is 1) |
 | ''​(''​ and ''​)'' ​   | Brackets/​parentheses (causes an expression to be evaluated earlier). | ''​(5 + 10) * 2''​ (is 30, not 25) | | ''​(''​ and ''​)'' ​   | Brackets/​parentheses (causes an expression to be evaluated earlier). | ''​(5 + 10) * 2''​ (is 30, not 25) |
 +
 +==== A note about modulo ====
 +
 +Modulo may seem somewhat obtuse an operator, but think of it like this: if you had a sequence of numbers: ''​0,​ 1, 2, 3, 4, 5, 6...'',​ and you did ''​% 3''​ to each of them, they would become ''​0,​ 1, 2, 0, 1, 2, 0...''​ - that is, a constantly looping sequence. This ability to simplify rising sequences allows you to perform some otherwise complicated calculations easily. See the [[function#​visited_string_string|visited()]] function for one such example.
 +
 +==== Strings of text ====
  
 You can also use **strings** in an expression. A string is a bunch of characters strung together, demarcated by matching pairs of either double or single quotes. You can use strings in expressions:​ You can also use **strings** in an expression. A string is a bunch of characters strung together, demarcated by matching pairs of either double or single quotes. You can use strings in expressions:​
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 Strings can thus be considered a "​contagious"​ data type - when they are added to other data types, the other data type becomes a string. Strings can thus be considered a "​contagious"​ data type - when they are added to other data types, the other data type becomes a string.
  
-(One upshot of this is that you can convert a number to a string by simply adding the "empty string"​ to it - a string with zero characters, just two quotation marks with nothing between:+(One upshot of this is that you can **convert** a number to a string by simply adding the "empty string"​ to it - a string with zero characters, just two quotation marks with nothing between:
  
 <​code>​ <​code>​
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 Usually, though, there isn't much call for this - numbers are generally as useful as strings.) Usually, though, there isn't much call for this - numbers are generally as useful as strings.)
 +
 +==== Printing Lists ====
 +
 +If you have a list, you can print the contents separated by a comma like so:
 +
 +    <<set $myarray = ["​this",​ "​that"​]>>​
 +    <<​print $myarray.join(",​ "​)>>​
 +
 +This will print the following:
 +
 +     ​this,​that
 +
 +
 +If you have specific questions about using lists in Twine, the [[frequently_asked_questions#​how_do_i_get_things_in_and_out_of_a_list_variable|FAQ]] may help.
 +
  
 ==== Functions ==== ==== Functions ====
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 | "Some text", "​2",​ "​true",​ 'More text', '​4',​ '​true'​ | **Strings**:​ snippets of text characters that can be [[<<​print>>​]]ed,​ joined up, or compared. Note that "​2"​ and "​true"​ resemble other types but are nonetheless strings. | | "Some text", "​2",​ "​true",​ 'More text', '​4',​ '​true'​ | **Strings**:​ snippets of text characters that can be [[<<​print>>​]]ed,​ joined up, or compared. Note that "​2"​ and "​true"​ resemble other types but are nonetheless strings. |
 | 0, 2, 5, -11, 45.25, Infinity | **Numbers** that can be used in arithmetic calculations. ''​Infinity''​ isn't really a number, but has the special property that it's always ''>''​ and ''>​=''​ every actual number, so you can use it in that case. (The same applies to ''​-Infinity''​ and ''<''/''<​=''​) | | 0, 2, 5, -11, 45.25, Infinity | **Numbers** that can be used in arithmetic calculations. ''​Infinity''​ isn't really a number, but has the special property that it's always ''>''​ and ''>​=''​ every actual number, so you can use it in that case. (The same applies to ''​-Infinity''​ and ''<''/''<​=''​) |
-| true, false | **Logical values**, created using the logical operators, and commonly used with to the [[<<​if>>​]] macro. True and false are the only values of this type. |+| true, false | **Logical values**, created using the logical operators, and commonly used with to the [[<<​if>>​]] macro. True and false are the only values of this type. 
 + 
 +<- [[display|Displaying A Passage Within Another]] --------- [[function|About Functions]]->​
expression.1406116190.txt.gz · Last modified: 2017/10/09 20:37 (external edit)