I always read that as the default behaviour for the language. C is usually compi...

smitherfield · on Oct 4, 2017

>Perl (<=5) is almost always interpreted but there are tools to turn Perl code into an executable.

IIRC those tools (of which similar ones exist for Java, Python, Ruby, Node.js, Lua and so on) just package together the sources (precompiled to bytecode) and an instance of the Perl[5] interpreter.

sigjuice · on Oct 4, 2017

Here's Java getting compiled to actual x86-64 code (mov $0x2a,%edx; add %edx,%eax).

  $ cat FortyTwo.java 
  public class FortyTwo
  {
          public static int fortytwo(int x) {
          	return x + 42;
          }
  }
  
  $ gcj-4.9 -c FortyTwo.java

$ objdump -S FortyTwo.o

  FortyTwo.o:     file format elf64-x86-64
   
   
  Disassembly of section .text:

  <snip>
    
  0000000000000022 <_ZN8FortyTwo8fortytwoEJii>:
  {
          public static int fortytwo(int x) {
          	return x + 42;
    22:	55                   	push   %rbp
    23:	48 89 e5             	mov    %rsp,%rbp
    26:	48 83 ec 20          	sub    $0x20,%rsp
    2a:	89 7d ec             	mov    %edi,-0x14(%rbp)
    2d:	b8 00 00 00 00       	mov    $0x0,%eax
    32:	48 89 c7             	mov    %rax,%rdi
    35:	b8 00 00 00 00       	mov    $0x0,%eax
    3a:	e8 00 00 00 00       	callq  3f <_ZN8FortyTwo8fortytwoEJii+0x1d>
    3f:	8b 45 ec             	mov    -0x14(%rbp),%eax
    42:	89 45 fc             	mov    %eax,-0x4(%rbp)
    45:	8b 45 fc             	mov    -0x4(%rbp),%eax
    48:	ba 2a 00 00 00       	mov    $0x2a,%edx
    4d:	01 d0                	add    %edx,%eax
    4f:	c9                   	leaveq 
    50:	c3                   	retq

smhenderson · on Oct 5, 2017

I also remember tools that simply converted Perl code to C. The argument against being that the advantages of an executable would be outweighed by the disadvantages of transpiled C being very inefficient.

sigjuice · on Oct 5, 2017

"Transpile" is not a real and meaningful word. Can we stop using it please? Btw, if you have relevant citations stating otherwise (Wikipedia isn't it), I am happy to be proven wrong. Thanks!