NML:Elementary values

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Elementary values

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Deprecated syntax

Changes from NML 0.2 to 0.3

Changes from NML 0.3 to 0.4

Changes from NML 0.4 to 0.5

Vehicles, Stations, Canals, Bridges, Towns, Houses, Industries (Tiles), Cargos, Airports+Tiles, Objects, Railtypes, Roadtypes, Tramtypes, Roadstops, Terrain

NML Tutorial

Expressions

Elementary values

Builtin functions

Elementary values in expressions are

Element	Syntax (Python RE)	Description
Decimal number	[0-9]+	one or more digits
Hexadecimal number	0x[0-9A-Fa-f]+	"0x" followed by one or more hexadecimal digits
Floating point number	[0-9]+\.[0-9]+	a decimal number, a dot, and another decimal number. Only supported for some properties that expect a floating point number.
Identifier	[a-zA-Z_][a-zA-Z0-9_]*	a letter or underscore, optionally followed by more letters, digits, or underscore characters
String	"([^"\\]|\\.)*"	A double quote character, followed by zero or more characters, ending with another double quote character. A character in-between is any single character except a double quote or a back-slash ("\"). It can also be "\\", "\n", "\t", or "\[0-9A-Fa-f][0-9A-Fa-f]" (a back-slash followed by exactly two hexadecimal digits).
Setting	an Identifier	The name of a GRF setting
Parameter	param[<num>]	Read/write the parameter with the given number.
Parameter from another GRF	param[<grfid>, <num>]	Read the value of a parameter of another grf
Unit	mph|km/h|m/s|hp|kW|hpI|hpM|tons|ton|kg	See the section on units.

You can combine those elementary values using operators like you're used to from other languages. The following operators are supported:

• Arithmetic operators: +, -, *, /, %
• Bitwise/logic operators: &, |, ^, &&, ||, <<, >>
• Comparison operators: ==, !=, <=, >=, <, >

Ternary operator

A ternary operator is provided (for integers only) in the form:

condition ? branch if true : branch if false

The ternary operator should be used with caution:

• it can be inefficient in certain cases as it executes both branches
• it is only safe for readonly operations (i.e. cannot be used with expressions like STORE_TEMP or STORE_PERM)