Allow relation symbols with parameters

Parameters must follow the relation symbol and be surrounded by braces, like so: `\rel{x}{y}{z}`.

This attempt is still brittle/broken in a few ways:
- It makes using braces in creative ways in mixfix notation ambiguous.
- It does not verify that the parameters are used in a consistent manner for each symbol. It essentially allows users to define  `a\MyRel b` and `a\MyRel{x} b` (and ones with even more parameters).
- It allows parameters for all relation symbols, even for those where it makes no sense in ordinary TeX markup, e.g. `a <{x} b`.

1 files changed, 7 insertions, 7 deletions

diff --git a/test/golden/coord/parsing.golden b/test/golden/coord/parsing.golden
index 65fa82f..a2b6657 100644
--- a/test/golden/coord/parsing.golden
+++ b/test/golden/coord/parsing.golden
@@ -31,7 +31,7 @@
                     ) Positive
                     ( RelationSymbol
                         ( Symbol "=" )
-                    )
+                    ) []
                     ( ExprVar
                         ( NamedVar "x" ) :| []
                     )
@@ -64,7 +64,7 @@
                     ) Positive
                     ( RelationSymbol
                         ( Symbol "=" )
-                    )
+                    ) []
                     ( ExprVar
                         ( NamedVar "x" ) :| []
                     )
@@ -97,7 +97,7 @@
                     ) Positive
                     ( RelationSymbol
                         ( Symbol "=" )
-                    )
+                    ) []
                     ( ExprVar
                         ( NamedVar "x" ) :| []
                     )
@@ -140,7 +140,7 @@
                     ) Positive
                     ( RelationSymbol
                         ( Symbol "=" )
-                    )
+                    ) []
                     ( ExprVar
                         ( NamedVar "x" ) :| []
                     )
@@ -190,7 +190,7 @@
                     ) Positive
                     ( RelationSymbol
                         ( Symbol "=" )
-                    )
+                    ) []
                     ( ExprVar
                         ( NamedVar "x" ) :| []
                     )
@@ -265,7 +265,7 @@
                     ) Positive
                     ( RelationSymbol
                         ( Symbol "=" )
-                    )
+                    ) []
                     ( ExprVar
                         ( NamedVar "x" ) :| []
                     )
@@ -291,7 +291,7 @@
                         ) Positive
                         ( RelationSymbol
                             ( Symbol "=" )
-                        )
+                        ) []
                         ( ExprVar
                             ( NamedVar "y" ) :| []
                         )