Module expr Copy item path Source All A [Step] that consumes a list of expressions and only
matches if all the child Expr AnchorEnd A Step AnchorStart A Step ExprMap A map from an Expr FirstMatchOf A naive expr collection that naively iterates through a list of patterns,
returning the first one that matches. FixedPhrase Matches a fixed sequence of tokens as they appear in the input.
Case-insensitive for words but maintains exact matching for other token types. LongestMatchOf A [Step] that returns the farthest offset of the longest match in a list of expressions. MergeableWords A Expr Optional An optional expression.
Forces the optional expression to always return Some by transmuting None into
Some(cursor..cursor). ReflexivePronoun Matches reflexive pronouns with configurable strictness. Repeating An expression that will match one or more repetitions of the same expression. SequenceExpr SimilarToPhrase SpaceOrHyphen Matches either a space or a hyphen, useful for matching compound words. SpelledNumberExpr Matches spelled-out numbers from one to ninety-nine TimeUnitExpr Matches a time unit. UnlessStep Provides the ability to use an expression as a condition.
If the condition does not match , it will return the result of the provided step. WordExprGroup An expression collection to look for expressions that start with a specific
word. Expr A common problem in Harper is that we need to identify tokens that fulfil certain criterion.
An Expr is a way to express whether a certain set of tokens fulfil that criteria.
When supplied a specific position in a token stream, the job of an Expr is to determine the window of tokens (including the cursor itself) that fulfils whatever criteria the author desires.
It is then the job of another system to identify portions of documents that fulfil this criteria. ExprExt OwnedExprExt Step An atomic step within a larger expression.