Difference between revisions of "String expansion"
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== What is switched == | == What is switched == | ||
| − | If the text is a [mission_variable], a [local_variable] or a system variable like [shipsFound_number], the content is replaced by the content of that variable. If not it looks at the key's in the [[ | + | If the text is a [mission_variable], a [local_variable] or a system variable like [shipsFound_number], the content is replaced by the content of that variable. If not it looks at the key's in the [[descriptions.plist]]. If it finds a match it uses one of the strings belonging to that key for switching. (Note that OXP-specific entries in descriptions.plist and missiontext.plist should have an OXP or creator-specific prefix to ensure uniqueness.) |
If you use [0] till [32] the number is replaced by strings from the "System Descriptions" key of the descriptions.plist inside Oolite itself. [0] is the first set of 5 arrays, [1] the second and so on. This was not meant for OXP use but a few numbers are still suitable. | If you use [0] till [32] the number is replaced by strings from the "System Descriptions" key of the descriptions.plist inside Oolite itself. [0] is the first set of 5 arrays, [1] the second and so on. This was not meant for OXP use but a few numbers are still suitable. | ||
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== When are things switched == | == When are things switched == | ||
Oolite calls only at certain places the switching routine. | Oolite calls only at certain places the switching routine. | ||
| − | *The most often used place is in [[missiontext.plist]]. In every text line the text between brackets is replaced by a variable or a [[ | + | *The most often used place is in [[missiontext.plist]]. In every text line the text between brackets is replaced by a variable or a [[descriptions.plist]] entry. |
| − | *Inside a [[ | + | *Inside a [[descriptions.plist]] entry you can also use brackets. This way you can get a recursive process. Look for example in the description.plist inside Oolite were it generates random names in a recursive way. (Recursion is limited to 32 times to prevent infinite looping.) |
*During evaluation of a AI.plist it only uses the switching on the content of a "commsMessage". | *During evaluation of a AI.plist it only uses the switching on the content of a "commsMessage". | ||
*During evaluation of a [[script.plist]] all the lines in the DO or ELSE part of a condition statement are switched. For some reason nothing is switched in the CONDITIONS part of a command so you can not use anything in brackets there. | *During evaluation of a [[script.plist]] all the lines in the DO or ELSE part of a condition statement are switched. For some reason nothing is switched in the CONDITIONS part of a command so you can not use anything in brackets there. | ||
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addSystemShips: my_ship 1 0.46 | addSystemShips: my_ship 1 0.46 | ||
| − | This line will then be executed and the ship is placed at the calculated random position. You can also define a [[ | + | This line will then be executed and the ship is placed at the calculated random position. You can also define a [[descriptions.plist]] entry of my_random_ship and define a list of several ships roles. When you then use: |
addSystemShips: [my_random_ship] 1 0.[d100_number] | addSystemShips: [my_random_ship] 1 0.[d100_number] | ||
the system will randomly pick a ship from the list and replace the d100_number for a value and returns the expanded string. This will than be excecuted. | the system will randomly pick a ship from the list and replace the d100_number for a value and returns the expanded string. This will than be excecuted. | ||
[[Category:Oolite scripting]] | [[Category:Oolite scripting]] | ||
Revision as of 15:11, 12 January 2013
Format
Oolite has a mechanism to replace text in strings by other text. At some places during script evaluation oolite searches for text between the square brackets []. If it finds this, it treats the text between the brackets as a kind of variable and tries to switch it, including the brackets fore the new text.
What is switched
If the text is a [mission_variable], a [local_variable] or a system variable like [shipsFound_number], the content is replaced by the content of that variable. If not it looks at the key's in the descriptions.plist. If it finds a match it uses one of the strings belonging to that key for switching. (Note that OXP-specific entries in descriptions.plist and missiontext.plist should have an OXP or creator-specific prefix to ensure uniqueness.)
If you use [0] till [32] the number is replaced by strings from the "System Descriptions" key of the descriptions.plist inside Oolite itself. [0] is the first set of 5 arrays, [1] the second and so on. This was not meant for OXP use but a few numbers are still suitable.
When are things switched
Oolite calls only at certain places the switching routine.
- The most often used place is in missiontext.plist. In every text line the text between brackets is replaced by a variable or a descriptions.plist entry.
- Inside a descriptions.plist entry you can also use brackets. This way you can get a recursive process. Look for example in the description.plist inside Oolite were it generates random names in a recursive way. (Recursion is limited to 32 times to prevent infinite looping.)
- During evaluation of a AI.plist it only uses the switching on the content of a "commsMessage".
- During evaluation of a script.plist all the lines in the DO or ELSE part of a condition statement are switched. For some reason nothing is switched in the CONDITIONS part of a command so you can not use anything in brackets there.
The way thing work means that you can create complicated structures. You can use for example:
addSystemShips: my_ship 1 0.[d100_number]
Oolite first offers above line to the replacement routine. That one replaces [d100_number] by a random number. e.g. 46. Than the routine returns:
addSystemShips: my_ship 1 0.46
This line will then be executed and the ship is placed at the calculated random position. You can also define a descriptions.plist entry of my_random_ship and define a list of several ships roles. When you then use:
addSystemShips: [my_random_ship] 1 0.[d100_number]
the system will randomly pick a ship from the list and replace the d100_number for a value and returns the expanded string. This will than be excecuted.
