Tarma Installer extensionsBoth Tarma Installer and Windows Installer allow the use of conditional expressions in many places. The syntax for these conditional expressions is based on the MSI syntax, with some extensions for Tarma Installer.
The conditional expression syntax is defined as follows; this also defines (implicitly) the order of precedence of the various constructs. You can override the order of precedence by enclosing a term in parentheses.
value ::= symbol | literal | integer relop ::= < | <= | > | >= | = | <> | >< | << | >> | ~relop term ::= value | value relop value | ( imp-term ) not-term ::= term | NOT term and-term ::= not-term | not-term AND and-term or-term ::= and-term | and-term OR or-term xor-term ::= or-term | or-term XOR xor-term eqv-term ::= xor-term | xor-term EQV eqv-term imp-term ::= eqv-term | eqv-term IMP imp-term symbol ::= varname | varref | %envvar | $compname | ?compname | &featname | !featname literal ::= "...any text..." integer ::= ...sequence of decimal digits... | 0x...sequence of hexadecimal digits... varname ::= ...name of a product variable (case-insensitive)... varref ::= ...symbolic expression enclosed in < and > (case-insensitive)... envvar ::= ...environment variable name (case-insensitive)... compname ::= ...component name (case-insensitive)... featname ::= ...feature name (case-insensitive)...
Tarma Installer extensionsTarma Installer allows the use of all symbolic expressions as part of conditional expressions. You can therefore also perform registry and INI file lookup (<@reg_path> and <#file?section?value>), retrieve file and component paths (<#file_alias> and <$comp_name>), and execute symbolic functions such as $fverpcmp as part of conditional expressions. It also means that the following are equivalent for Tarma Installer:
None of these extensions are supported by Windows Installer, so if you plan to build a Windows Installer package, you should restrict your conditional expressions to the common subset (i.e., the items that are NOT underlined in the syntax description).
Note: To prevent confusion between symbolic expressions and some of the relational operators, you should place spaces on either side of a relational operator. For example, use TsuRunMode < 0 rather than TsuRunMode<0.
The following logical operators are defined. Their names are case-insensitive.
| Operator | Meaning |
|---|---|
| NOT | Negates the value of its operand. |
| AND | True if both operands are True. |
| OR | True if at least one of its operands is True. |
| XOR | True if exactly one of its operands is True. |
| EQV | True if its operands are both True or both False. |
| IMP | True if its left operand is False or its right operand is True. |
The following relational operators are defined. Their meaning depends on the type of their operands:
This means, for example, that the expression TsuRunMode > 0 is evaluated with an integer comparison, while TsuRunMode > "0" uses a string comparison.
| Operator | Integer | String |
|---|---|---|
| < | True if the left operand is numerically less than the right operand. | True if the left operand sorts before the right operand. |
| <= | True if the left operand is numerically less than or equal to the right operand. | True if the left operand sorts before or is equal to the right operand. |
| > | True if the left operand is numerically greater than the right operand. | True if the left operand sorts after the right operand. |
| >= | True if the left operand is numerically greater than or equal to the right operand. | True if the left operand sorts after or is equal to the right operand. |
| = | True if the left operand is equal to the right operand. | True if the left operand is equal to the right operand. |
| <> | True if the left operand is not equal to the right operand. | True if the left operand is not equal to the right operand. |
| >< | True if the left and right operands have any bits in common (binary AND). | True if the left operand contains the right operand. |
| << | True if the 16 most significant bits of the (32-bit) left operand are equal to the right operand (HIWORD). | True if the left operand starts with the right operand. |
| >> | True if the 16 least significant bits of the left operand are equal to the right operand (LOWORD). | True if the left operand ends with the right operand. |
| ~ (as prefix) | Not allowed | Makes the comparison case-insensitive. |
The following prefixes can be used on symbol items.
| Symbol prefix | Operand | Result |
|---|---|---|
| % | Name of environment variable | Value of the environment variable |
| $ | Name of component | Component action (see below) |
| ? | Name of component | Component state (see below) |
| & | Name of feature | Feature action (see below) |
| ! | Name of feature | Feature state (see below) |
The following values are returned for the component and feature actions and states:
| Value | Action | State |
|---|---|---|
| -1 | No action | State is unknown |
| 1 | Feature will be advertised | Feature is advertised |
| 2 | Component/feature will be removed | Component/feature is not present |
| 3 | Component/feature will be installed locally | Component/feature is installed locally |
| 4 | Component/feature will be installed to run from source | Component/feature runs from source |