Devember/log13.txt

   1 Call realloc() to double the size,
   2 or at least to multiply it by a constant factor.
   3 It is common wisdom among programmers, and it even works!
   4
   5 I discovered minish supports relative path, because execv() does.
   6
   7 I have added what I consider the killer feature of minish:
   8 command substitution.
   9 Many shells do it, but minish, in my opinion, does it right.
  10 If a command contains parentheses,
  11 what is inside is executed and its output substitutes it.
  12
  13 Let us suppose there is a program named “echo” in the current directory
  14 that outputs its arguments separated by ␀.
  15 Input                                   Output (I have tested it!)
  16 ./echo␀hello                            hello
  17 ./echo␀./echo␀hello                     ./echo␀hello
  18 ./echo␀(./echo␀hello)                   hello
  19 ./echo␀(./echo␀hello) (./echo␀world)    hello world
  20 ./echo␀h(./echo␀ell)o␀world             hello␀world
  21 (./echo␀./echo␀hello)                   hello
  22
  23 Splicing is automatic:
  24 if the output of the substituted command contains ␀,
  25 it is automatically separated into multiple words.
  26 This is always the desired behavior,
  27 because ␀ cannot appear inside a word.
  28
  29 There is a subtle difference between using command substitution
  30 and typing the command yourself:
  31 the special characters “(”, “)”, and newline
  32 lose their special meaning.
  33 This is by design and it is very important. I will show you tomorrow.
  34
  35 Enough for today.
  36
  37 Suggested readings:
  38 https://computerworld.com.au/article/279011/
  39 https://fishshell.com/docs/current/design.html
  40 https://elvish.io/ref/philosophy.html