feat: Updating .pest grammar to support Special Order Sets

dandxy89 · Nov 12, 2023 · 191a55e · 191a55e
1 parent 33153be
commit 191a55e
Showing 1 changed file with 9 additions and 3 deletions.
diff --git a/src/lp_file_format.pest b/src/lp_file_format.pest
@@ -47,7 +47,7 @@ VALID_CHARS = _{
   | "~"
 }
 VARIABLE    = ${
-    !(FREE | END | CONSTRAINT_SECTION | BOUND_SECTION | GENERALS_SECTION | BINARIES_SECTION | SEMI_CONTINUOUS_SECTION) ~ VALID_CHARS{1, 255}
+    !(FREE | END | SOS_SECTION | CONSTRAINT_SECTION | BOUND_SECTION | GENERALS_SECTION | BINARIES_SECTION | SEMI_CONTINUOUS_SECTION) ~ VALID_CHARS{1, 255}
 }
 
 // Problem Name
@@ -133,14 +133,20 @@ BINARIES         =  { NEWLINE ~ BINARIES_SECTION ~ (NEWLINE? ~ VARIABLE)* }
 SEMI_CONTINUOUS_SECTION = _{ ^"SEMI" ~ (^"S" | ^"-CONTINUOUS") }
 SEMI_CONTINUOUS         =  { NEWLINE ~ SEMI_CONTINUOUS_SECTION ~ (NEWLINE? ~ VARIABLE)* }
 
-// SOS: Special Ordered Sets
+// SOS: Special Ordered Set
+SOS_SECTION         = _{ ^"SOS" }
+TYPE1               =  { "S1::" }
+TYPE2               =  { "S2::" }
+VARIABLE_AND_WEIGHT =  { VARIABLE ~ ":" ~ FLOAT }
+SOS_CONSTRAINT      =  { NEWLINE? ~ (CONSTRAINT_NAME ~ COLON?)? ~ (TYPE1 | TYPE2) ~ VARIABLE_AND_WEIGHT* }
+SOS                 =  { NEWLINE ~ SOS_SECTION ~ SOS_CONSTRAINT+ }
 
 // End of file
 // https://www.ibm.com/docs/en/icos/22.1.1?topic=representation-end-file-in-lp-file-format
 EOF = _{ NEWLINE* ~ END }
 
 // Global
-OPTIONAL_SECTIONS = _{ BOUNDS? ~ INTEGERS? ~ GENERALS? ~ BINARIES? ~ SEMI_CONTINUOUS? ~ EOF? }
+OPTIONAL_SECTIONS = _{ BOUNDS? ~ INTEGERS? ~ GENERALS? ~ BINARIES? ~ SEMI_CONTINUOUS? ~ SOS? ~ EOF? }
 LP_FILE           =  {
     LP_PROBLEM_NAME? ~ COMMENTS* ~ PROBLEM_SENSE ~ OBJECTIVES ~ CONSTRAINTS ~ OPTIONAL_SECTIONS
 }