diff options
Diffstat (limited to 'src/main/java/bjc/rgens/parser/elements/DependantRuleReference.java')
| -rw-r--r-- | src/main/java/bjc/rgens/parser/elements/DependantRuleReference.java | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/src/main/java/bjc/rgens/parser/elements/DependantRuleReference.java b/src/main/java/bjc/rgens/parser/elements/DependantRuleReference.java new file mode 100644 index 0000000..5eccf8e --- /dev/null +++ b/src/main/java/bjc/rgens/parser/elements/DependantRuleReference.java @@ -0,0 +1,48 @@ +package bjc.rgens.parser.elements; + +import bjc.rgens.parser.GrammarException; +import bjc.rgens.parser.GenerationState; + +import java.util.regex.Matcher; +import java.util.regex.Pattern; + +public class DependantRuleReference extends RuleCaseElement { + private static Pattern NAMEVAR_PATTERN = Pattern.compile("\\$(\\w+)"); + + public DependantRuleReference(String vl) { + super(vl, ReferenceType.DEPENDENT); + } + + @Override + public void generate(GenerationState state) { + String refBody = val.substring(1, val.length() - 1); + + /* Handle dependent rule names. */ + StringBuffer nameBuffer = new StringBuffer(); + + Matcher nameMatcher = NAMEVAR_PATTERN.matcher(refBody); + + while (nameMatcher.find()) { + String var = nameMatcher.group(1); + + if (!state.vars.containsKey(var)) { + String msg = String.format("No variable '%s' defined", var); + throw new GrammarException(msg); + } + + String name = state.vars.get(var); + + if (name.contains(" ")) { + throw new GrammarException("Variables substituted into names cannot contain spaces"); + } else if (name.equals("")) { + throw new GrammarException("Variables substituted into names cannot be empty"); + } + + nameMatcher.appendReplacement(nameBuffer, name); + } + + nameMatcher.appendTail(nameBuffer); + + doGenerate(String.format("[%s]", nameBuffer.toString()), state); + } +} |
