Goto statements ought not to be¹¹ Equivalently: “oughtn’t be”, “should not be”, “shouldn’t be”. used in high-level programs.²²The programs under Dijkstra’s consideration were imperative programs only.

The analysis applies to sequential processes where the order of evaluation matters. As such situations where the order of evaluation does not matter, e.g., “functionally pure” portions of an algorithm, the case against the Goto statement falls apart.

The paper shows that using the Goto statement comes at a cost. It claims that this cost is significant.

• Claims: the sequential execution (process) of a program is the main thing of interest. The program is a means to this end.
• Claims: given a stage in a sequential process it is important to know what has happened and what hasn’t yet happened.
• Shows: given a Goto program³³A program using the Goto statement. and coordinates⁴⁴ Here a coordinate is some combination of grounding of terms that are manifested in the program text (e.g., line 23; [line 21, line 56, line 14]; [line 23, i=10, line 26]). corresponding to two process states it is not possible to know which state is before the other.

Per Wikipedia:

Considered harmful was popularized among computer scientists by Edsger Dijkstra’s letter “Go To Statement Considered Harmful”,[3]​[4]​ published in the March 1968 Communications of the ACM (CACM), in which he criticized the excessive use of the GOTO statement in programming languages of the day and advocated structured programming instead.[5]​ The original title of the letter, as submitted to CACM, was “A Case Against the Goto Statement”, but CACM editor Niklaus Wirth changed the title to “Go To Statement Considered Harmful”.[6]​ Regarding this new title, Donald Knuth quipped that “Dr. Goto cheerfully complained that he was always being eliminated.”[7]​

Frank Rubin published a criticism of Dijkstra’s letter in the March 1987 CACM where it appeared under the title “‘GOTO Considered Harmful’ Considered Harmful”.[8]​ The May 1987 CACM printed further replies, both for and against, under the title “’”GOTO Considered Harmful“ Considered Harmful’ Considered Harmful?”.[9]​ Dijkstra’s own response to this controversy was titled On a Somewhat Disappointing Correspondence.[10]​

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Suhail’s outline of "A Case Against the Goto Statement"https://t.co/TLiRGQSKMB

Chris’ outline of "A Case Against the Goto Statement"https://t.co/7LEdaLGXLq

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