Write a Stepping Quine

Question

Related

Your goal, is to write a set of programs, that progresses from one to the other, one character at a time. For example. Given the starting program abcd and the ending program wxyz, you should have 5 valid programs, with the respective outputs.

abcd -> wbcd
wbcd -> wxcd
wxcd -> wxyd
wxyd -> wxyz
wxyz -> wxyz

As can be seen, the last program should be a quine.

Rules

• Your start and end program may be any length, And they may also be different lengths
• Your start and end program must contain entirely unique characters at each position, but may share characters overall.
• Each program should affect a single character at a time, in any order, characters should only be added or removed from the end of the program.
• None of your programs need to follow the valid quine rules, they only need to output the correct string.
• Standard Loopholes Apply.

Scoring

Programs are scored by the length of the start program plus the length of the end program in bytes. In the previous example, 4 + 4 = 8, so the score is eight. This is code-golf, so shortest programs wins.

Some Valid Programs

In languages that hopefully don't exist

abcd -> dbcd -> dccd -> dcbd -> dcba
a -> b
a -> b -> bc -> bcd -> bcde
ab -> aa -> ba
[BLANK PROGRAM] -> a
xyz -> xy -> x -> [BLANK PROGRAM]

• FryAmTheEggman: If the scoring isn't exactly "length of the code" you should use code-challenge instead.
• ATaco: I'd disagree, as it's just the length of 2 programs. It's still very much so a golfing challenge.
• Stewie Griffin: BLANK PROGRAM is zero bytes right (thus disallowed according to your first rule?)
• ATaco: I knew I was going to condradict myself somewhere, fixed. @StewieGriffin
• Unrelated String: I feel like maybe this should have been code-bowling, since the shorter an answer is, the fewer stages it needs to go through before reaching the end program.

Answer 1

Retina, Score 1

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• The empty program outputs 1, since the empty input matches the empty string exactly once.
• 1 outputs 0, since 1 doesn't match the empty input.
• 0 outputs 0, since 0 doesn't match the empty input. Since it outputs itself, it's a quine (as defined in this challenge).

• Martin Ender: You'd technically need to use the latest Retina commit, because the version on TIO still prints trailing linefeeds by default.
• Martin Ender: And I think the empty program is allowed, see the second-to-last example in the challenge.
• Ørjan Johansen: @MartinEnder The OP was self-contradictory on this when this answer was posted.
• Martin Ender: @ØrjanJohansen which is why I've informed Stewie that it's now been clarified and the answer can be updated. :)
• Ørjan Johansen: @MartinEnder Yeah but the examples didn't change, only the part contradicting them.

Answer 2

05AB1E, Score 1

=

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= prints top of stack (nothing) without newline.

(empty program) also generates no output.

Boring solution, but it works.

Answer 3

Braingolf, Score 2

/

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Niladic / pushes 5, with implicit output, 5 also pushes 5.

Answer 4

Japt, Score 2

T

Output: 0 (Test it)

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0

Output: 0 (Test it)

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Any uppercase letter after T would also work in the same way.