Do a depth-first traversal of NODES along NODE-EDGES, calling PROC with each node and the current result, and visiting each reachable node exactly once. NODES must be a list of nodes, and NODE-EDGES must be a one-argument procedure as returned by 'node-edges' or 'node-back-edges'.

Return, as a monadic value, a one-argument procedure that, given a node of TYPE, returns its edges. NODES is taken to be the sinks of the global graph.

Return the list of nodes directly or indirectly connected to NODES according to the NODE-EDGES procedure. NODE-EDGES must be a one-argument procedure that, given a node, returns its list of direct dependents; it is typically returned by 'node-edges' or 'node-back-edges'.

Write to PORT the representation of the DAG with the given SINKS, using the given BACKEND. Use NODE-TYPE to traverse the DAG. When REVERSE-EDGES? is true, draw reverse arrows. Do not represent nodes whose distance to one of the SINKS is greater than MAX-DEPTH.

Return true if FILE matches a version control system from the list VCSES-DIRECTORIES.

Return a two-argument procedure that returns true when version-control metadata directories such as '.git' is found in DIRECTORY.

Compute the hash of FILE with ALGORITHM.

Symbolic links are only dereferenced if RECURSIVE? is false. Directories are only supported if RECURSIVE? is #true or 'auto'. The executable bit is only recorded if RECURSIVE? is #true. If FILE is a symbolic link, it is only followed if RECURSIVE? is false.

For regular files, there are two different hashes when the executable hash isn't recorded: the regular hash and the nar hash. In most situations, the regular hash is desired and setting RECURSIVE? to 'auto' does the right thing for both regular files and directories.

This procedure must only be used under controlled circumstances; the detection of symbolic links in FILE is racy.

When FILE is a directory, the procedure SELECT? called as (SELECT? FILE STAT) decides which files to include. By default, version control files are excluded. To include everything, SELECT? can be set to (const #true).

Return the file-name for packages using hg-download.

Return the version string for packages using hg-download.

This procedure evaluates to a predicate that reports back whether a given file - stat combination is part of the files tracked by Mercurial.

Return a fixed-output derivation that fetches REF, a <hg-reference> object. The output is expected to have recursive hash HASH of type HASH-ALGO (a symbol). Use NAME as the file name, or a generic name if #f.

Send all of REQUESTS to the server at BASE-URI. Call PROC for each response, passing it the request object, the response, a port from which to read the response body, and the previous result, starting with SEED, à la 'fold'. Return the final result.

When PORT is specified, use it as the initial connection on which HTTP requests are sent; otherwise call OPEN-CONNECTION to open a new connection for a URI. When KEEP-ALIVE? is false, close the connection port before returning.