Timeline for What is the difference between \let and \def?
Current License: CC BY-SA 3.0
20 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| May 7, 2016 at 17:06 | comment | added | A Feldman | Thanks both for your original answer, which helped me better understand this very important topic., and for your expansion of your answer. | |
| May 7, 2016 at 12:38 | comment | added | Norman Gray | Thanks for your contributions, @a-feldman, but I'm not convinced they really clarify things. The underlying expansion idea is at heart very simple, and this was (deliberately) emphasised by the brevity of the answer. I have drafted similar remarks in the past, but on reflection deleted them from my edit before saving: I've redone this now in response to your implied request for expansion of the answer. | |
| May 7, 2016 at 12:35 | history | edited | Norman Gray | CC BY-SA 3.0 | Reverted additions; added some extra explanation |
| May 2, 2016 at 18:40 | comment | added | A Feldman | I searched for it to try to understand the topic better. I guess this question is really fundamental, and therefore likely to be revisited. Is this a good thing, that tex-core tag questions are being modified and "plopped up"? | |
| May 1, 2016 at 17:09 | comment | added | Johannes_B | For the last few weeks, tex-core and related tag questions have been modified and plopped up on the main site. There is also a Wikibook on TeX that needs some attention and one on LaTeX that needs even more attention. | |
| S May 1, 2016 at 17:07 | history | suggested | A Feldman | CC BY-SA 3.0 | Made clear when "point" is referred, that it point in time. |
| May 1, 2016 at 16:54 | review | Suggested edits | |||
| S May 1, 2016 at 17:07 | |||||
| S May 1, 2016 at 16:43 | history | edited | Yossi Gil | CC BY-SA 3.0 | In order to understand the example I had to annotate it. |
| S May 1, 2016 at 16:43 | history | suggested | A Feldman | CC BY-SA 3.0 | In order to understand the example I had to annotate it. |
| May 1, 2016 at 16:40 | review | Suggested edits | |||
| S May 1, 2016 at 16:43 | |||||
| May 3, 2015 at 15:26 | comment | added | Norman Gray | @NicholasHamilton It's a similar idea, yes, but that may be a slightly confusing way to think about it, since TeX is rather sui generis in programming language terms. A useful mental model is that TeX macros expand, and the expansion is than expanded, and... so on until the engine arrives at one of the relatively small number of primitives which actually do something, such as adding a box (possibly containing a letter or a paragraph) to a list of boxes. Lower-level TeX programming, and its headaches, is all about controlling what gets expanded when, and to what. | |
| Apr 30, 2015 at 20:06 | comment | added | Nicholas Hamilton | Awesome answer. I guess its a bit like assignment vs reference in other languages.... | |
| Apr 29, 2015 at 13:45 | history | edited | Norman Gray | CC BY-SA 3.0 | Fix long-unnoticed mis-spelling |
| Sep 2, 2014 at 3:42 | comment | added | dubiousjim | Here is some more discussion. | |
| Sep 1, 2014 at 23:15 | comment | added | dubiousjim | The closest analogue to \let\foo\bar along the lines @Didii is suggesting would be \expandafter\def\expandafter\foo\expandafter{\bar}. There remain differences even between these, as detailed in Martin Scharrer's answer. But for most purposes, I think they would have much the same effect. | |
| Jul 20, 2012 at 11:15 | comment | added | Norman Gray | With that definition, writing \foo\alpha at the bottom of the example would expand into \expandafter\bar\alpha; what that does is first expand \alpha, and then expand \bar (in this case to 'goodbye'). Using \expandafter counts as pretty advanced TeX, and is for the arcane cases where you need to control the order of evaluation in a non-default way. Try TeXing \def\baz{wibble} \def\x#1{-#1-} \x\baz \expandafter\x\baz | |
| Jul 20, 2012 at 9:59 | comment | added | Didii | Does this mean that \let\foo\bar is the same as \def\foo{\expandafter\bar}? Probably not, but why then? | |
| Jul 30, 2010 at 8:32 | history | edited | Norman Gray | CC BY-SA 2.5 | Nitpick: replace 'expanded' by 'evaluated' |
| Jul 27, 2010 at 22:50 | vote | accept | bryn | ||
| Jul 27, 2010 at 8:38 | history | answered | Norman Gray | CC BY-SA 2.5 |