diff options
Diffstat (limited to 'main/subexast.go')
-rw-r--r-- | main/subexast.go | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/main/subexast.go b/main/subexast.go new file mode 100644 index 0000000..7e2f33c --- /dev/null +++ b/main/subexast.go @@ -0,0 +1,117 @@ +package main + +import ( + "fmt" +) + +type SubexAST interface { + compileWith(next SubexState) SubexState +} + +type SubexASTConcat struct { + first, second SubexAST +} +func (ast SubexASTConcat) compileWith(next SubexState) SubexState { + return ast.first.compileWith(ast.second.compileWith(next)) +} +func (ast SubexASTConcat) String() string { + return fmt.Sprintf("(%v)(%v)", ast.first, ast.second) +} + +type SubexASTStore struct { + match RegexAST + slot rune +} +func (ast SubexASTStore) compileWith(next SubexState) SubexState { + return SubexStoreState { + match: ast.match.compileWith(RegexNoneState{}), + slot: ast.slot, + next: next, + } +} +func (ast SubexASTStore) String() string { + return fmt.Sprintf("$%c(%v)", ast.slot, ast.match) +} + +type SubexASTOr struct { + first, second SubexAST +} +func (ast SubexASTOr) compileWith(next SubexState) SubexState { + return SubexGroupState { + ast.first.compileWith(next), + ast.second.compileWith(next), + } +} + +type SubexASTMaximise struct { + content SubexAST +} +func (ast SubexASTMaximise) compileWith(next SubexState) SubexState { + state := &SubexGroupState { + nil, + next, + } + state.first = ast.content.compileWith(state) + return state +} +func (ast SubexASTMaximise) String() string { + return fmt.Sprintf("(%v)*", ast.content) +} + +type SubexASTMinimise struct { + content SubexAST +} +func (ast SubexASTMinimise) compileWith(next SubexState) SubexState { + state := &SubexGroupState { + next, + nil, + } + state.second = ast.content.compileWith(state) + return state +} +func (ast SubexASTMinimise) String() string { + return fmt.Sprintf("(%v)-", ast.content) +} + +type SubexASTRepeat struct { + content SubexAST + min, max int +} +func (ast SubexASTRepeat) compileWith(next SubexState) SubexState { + for i := ast.min; i < ast.max; i += 1 { + next = SubexGroupState { + ast.content.compileWith(next), + next, + } + } + for i := 0; i < ast.min; i += 1 { + next = ast.content.compileWith(next) + } + return next +} + +type SubexASTCopyRune rune +func (ast SubexASTCopyRune) compileWith(next SubexState) SubexState { + return SubexCopyRuneState{ + rune: rune(ast), + next: next, + } +} + +type SubexASTCopyAny struct {} +func (ast SubexASTCopyAny) compileWith(next SubexState) SubexState { + return SubexCopyAnyState{next} +} +func (ast SubexASTCopyAny) String() string { + return "." +} + +type SubexASTOutput struct { + replacement []TransducerOutput +} +func (ast SubexASTOutput) compileWith(next SubexState) SubexState { + return SubexOutputState{ + content: ast.replacement, + next: next, + } +} |