Computes matching algorithms quickly using Rcpp.
    Implements the Gale-Shapley Algorithm to compute the stable
    matching for two-sided markets, such as the stable marriage
    problem and the college-admissions problem. Implements Irving's
    Algorithm for the stable roommate problem. Implements the top
    trading cycle algorithm for the indivisible goods trading problem.

Selects matched samples of the original treated and
    control groups with similar covariate distributions -- can be
    used to match exactly on covariates, to match on propensity
    scores, or perform a variety of other matching procedures.  The
    package also implements a series of recommendations offered in
    Ho, Imai, King, and Stuart (2007) <DOI:10.1093/pan/mpl013>. (The 
    'gurobi' package, which is not on CRAN, is optional and comes with 
    an installation of the Gurobi Optimizer, available at 
    <https://www.gurobi.com>.)

Core functions as well as diagnostic and calibration tools for combining matching and linear regression for causal inference in observational studies.

Provides flexible dictionary-based
    cleaning that allows users to specify implicit and explicit missing data,
    regular expressions for both data and columns, and global matches, while
    respecting ordering of factors. This package is part of the 'RECON'
    (<https://www.repidemicsconsortium.org/>) toolkit for outbreak analysis.

Performs multilevel matches for data with cluster-
	level treatments and individual-level outcomes using a network 
	optimization algorithm.  Functions for checking balance at the 
	cluster and individual levels are also provided, as are methods 
	for permutation-inference-based outcome analysis.  Details in 
	Pimentel et al. (2018) <doi:10.1214/17-AOAS1118>.  The optmatch 
	package, which is useful for running many of the provided 
	functions, may be downloaded from Github at 
	<https://github.com/markmfredrickson/optmatch> if not available on 
	CRAN.

Inspired by pattern matching and enum types in Rust
    and many functional programming languages, this package offers
    an updated version of the 'switch' function called 'Match' that
    accepts atomic values, functions, expressions, and enum variants.
    Conditions and return expressions are separated by '->' and 
    multiple conditions can be associated with the same return expression
    using '|'. 'Match' also includes support for 'fallthrough'. The 
    package also replicates the Result and Option enums from Rust.