Type a statement and press Analyze.
Tokens
Every lexeme, the grammar terminal it becomes, and the rule that matched it.
Parse tree
The concrete syntax tree the LL(1) driver built. Click a node to fold it.
Parse trace
Stack, remaining input and action at every step of the predictive parse.
Leftmost derivation
The same parse replayed as sentential forms.
FIRST and FOLLOW
Computed over the grammar after left-recursion removal and left factoring.
Corpus and negative tests
Click any row to load it into the analyzer.
Statistics
Measured over the whole corpus by the same pipeline.