EAPI 5 supports ?? ( ) groups

See bug 354219

2 files changed, 37 insertions, 0 deletions

diff --git a/dependencies.tex b/dependencies.tex
index 8f78f3d..ff12299 100644
--- a/dependencies.tex
+++ b/dependencies.tex
@@ -66,6 +66,12 @@ be surrounded on both sides by whitespace, except at the start and end of the st
     parenthesis. More formally: \t{exactly-one-of ::= '\textasciicircum\textasciicircum' whitespace
     '(' whitespace (item whitespace)* ')'}.
     Permitted in \t{REQUIRED\_USE}.
+\item \featurelabel{at-most-one-of} An at-most-one-of group, which consists of the string \t{??},
+    followed by whitespace, followed by an open parenthesis, followed by whitespace, followed by
+    zero or more of (a dependency item of any kind followed by whitespace), followed by a close
+    parenthesis. More formally: \t{exactly-one-of ::= '??' whitespace '(' whitespace (item
+    whitespace)* ')'}. Permitted in \t{REQUIRED\_USE} in EAPIs listed in
+    table~\ref{tab:at-most-one-of-table} as supporting \t{REQUIRED\_USE ??}\ groups.
 \item A use-conditional group, which consists of an optional exclamation mark, followed by
     a use flag name, followed by a question mark, followed by whitespace, followed by
     an open parenthesis, followed by whitespace, followed by zero or more of (a dependency item
@@ -93,6 +99,23 @@ In particular, note that whitespace is not optional.
     \end{tabular}
 \end{centertable}
 
+\ChangeWhenAddingAnEAPI{5}
+\begin{centertable}{EAPIs supporting \t{REQUIRED\_USE ??}\ groups} \label{tab:at-most-one-of-table}
+    \begin{tabular}{ l l }
+        \toprule
+        \multicolumn{1}{c}{\textbf{EAPI}} &
+        \multicolumn{1}{c}{\textbf{Supports \t{REQUIRED\_USE ??}\ groups?}} \\
+        \midrule
+    \t{0} & No \\
+    \t{1} & No \\
+    \t{2} & No \\
+    \t{3} & No \\
+    \t{4} & No \\
+    \t{5} & Yes \\
+    \bottomrule
+    \end{tabular}
+\end{centertable}
+
 \subsection{All-of Dependency Specifications}
 
 In an all-of group, all of the child elements must be matched.
@@ -126,6 +149,16 @@ In an exactly-one-of group, exactly one immediate child element must be matched.
 
 An empty exactly-one-of group counts as being matched.
 
+\subsection{At-most-one-of Dependency Specifications}
+
+Any use-conditional group that is an immediate child of an at-most-one-of group, if not enabled
+(disabled for an exclamation mark prefixed use flag name), is not considered a member of the
+at-most-one-of group for match purposes.
+
+In an at-most-one-of group, at most one immediate child element must be matched.
+
+An empty at-most-one-of group counts as being matched.
+
 \subsection{Package Dependency Specifications}
 
 A package dependency can be in one of the following base formats. A package manager must warn or
diff --git a/eapi-differences.tex b/eapi-differences.tex
index 8ece012..3e4bf27 100644
--- a/eapi-differences.tex
+++ b/eapi-differences.tex
@@ -55,6 +55,9 @@
 \t{DEFINED\_PHASES} & \compactfeatureref{defined-phases} &
     Optionally & Optionally & Optionally & Optionally & Yes & Yes \\
 
+\t{?? ( ) groups} & \compactfeatureref{at-most-one-of} &
+    No & No & No & No & No & Yes \\
+
 \t{SRC\_URI} arrows & \compactfeatureref{src-uri-arrows} &
     No & No & Yes & Yes & Yes & Yes \\
 
@@ -248,6 +251,7 @@ EAPI 4 is EAPI 3 with the following changes:
 EAPI 5 is EAPI 4 with the following changes:
 
 \begin{compactitem}
+\item \t{REQUIRED\_USE} now supports \t{??} groups, \featureref{at-most-one-of}.
 \item Slot operator dependencies, \featureref{slot-operator-deps}.
 \item \t{USE} is calculated differently, \featureref{profile-iuse-injection}.
 \item \t{econf} adds \t{-{}-disable-silent-rules}, \featureref{econf-options}.