README.md

Ocaml metrics

Run tool:

ocaml_metrics <DIR> [-met-list <M1>,<M2>,<M3>] [-sec-list <L1>,<L2>,<L3>] [-v-list <V1>,<V2>,<V3>]

<DIR> - directory with dune-based project

-met-list <M1>,<M2>,<M3> - metrics to show (metrics is shown if it contains a substring from this list)

-sec-list <L1>,<L2>,<L3> - dune libraries and executables from project to analyze

-v-list <V1>,<V2>,<V3> - print verbose output of metrics groups from this list

Metrics names are printed in the following format: [metrics group id]_[metrics id].

Metrics group id	Description	Metrics id	Description
cohesion	Class cohesion metrics Alternative to class is a module. Alternative to both attributes and methods are functions. "Methods share attributes" -> "Functions call the same function or one of them calls the other"	LCOM1	Original definition: Number of pairs of methods that do not share attributes
		LCOM2	Original definition: P = Number of pairs of methods that do not share attributes Q = Number of pairs of methods that share attributes LCOM2 = max(P - Q, 0)
		LCOM34	LCOM3 = Number of disjoint components in the graph that represents each method as a node and the sharing of at least one attribute as an edge LCOM4 = Similar to LCOM3 and additional edges are used to represent method invocations In our interpretation LCOM3 and LCOM4 give the same values.
		LCOM5	Original definition: , where is the number of attributes, is the number of methods, and is the summation of the number of distinct attributes accessed by each method in a class Our interpretation: Instead of we use maximum possible number of edges in graph where nodes are functions and edges are used to represent one function calling another. When denominator is >= 0, LCOM5 is -1.
		COH	Original definition: , where , , and have the same definitions as above Our interpretation: Like in LCOM5.
coupling	Coupling metrics Note: Fan-in, Fan-out and APIU are calculated only for public modules; EXT is calculated for both modules and functions.	Fan-in	Number of modules that depend on given module
		Fan-out	Numbers of modules that the given module depends on
		APIU	API Function Usage Index. Suppose that module has public functions, in project other modules call one or more function from . or 0 if
		EXT	External method calls. Number of external functions called by a function or a module (only functions defined in the project are considered).
		AC	Association-Induced Coupling Metrics. M = modules in project; Mod_ext(m) = modules that have functions that use functions from m; F = functions in project; F(m) = functions in module m; Func_ext(m) = functions that use functions from m; Func_int(m) = functions in m that use functions from other modules in M;
CC-based	McCabe's cyclomatic complexity based Read more about CC: https://en.wikipedia.org/wiki/Cyclomatic_complexity	ord	Traditional cyclomatic complexity
		rec	CC-ord + [Number of recursive calls]
		mod	Modified cyclomatic complexity. Like CC-ord but count match E0 with | P1 -> E1 ... | PN -> EN as 1 decision point instead of (N - 1) (but still count guards).
		mod-ord-max	Maximum of CC-based_ord in module
		mod-ord-avg	Average of CC-based_ord in module
Halstead	Halstead complexity measures n1 = the number of distinct operators n2 = the number of distinct operands N1 = the total number of operators N2 = the total number of operands	n	Program vocabulary: n1 + n2
		N	Program length: N1 + N2
		V	Volume: N * log2(n)
		D	Difficulty: (n1 / 2) * (N2 / n2)
		E	Effort: V * D
LOC-based	Lines of code	all	Number of lines in function
		code	Exclude comment and blank lines