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Diffstat (limited to 'doc/manual.cli')
| -rw-r--r-- | doc/manual.cli | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/doc/manual.cli b/doc/manual.cli index 59084d6..0cd5a5e 100644 --- a/doc/manual.cli +++ b/doc/manual.cli @@ -8156,6 +8156,19 @@ target-specific variables. Typed variable values are converted to string using the corresponding \c{builtin.string()} function overload before substitution. +Using an undefined variable in a substitution is an error. Using a \c{null} +value in a substitution is also an error unless the fallback value is +specified with the \c{in.null} variable. For example: + +\ +# buildfile + +h{config}: in{config} +{ + in.null = '' # Substitute null values with empty string. +} +\ + A number of other build system modules, for example, \l{#module-version \c{version}} and \l{#module-bash \c{bash}}, are based on the \c{in} module and provide extended functionality. The \c{in} preprocessing rule matches any |