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On the contrary, I implemented a substantial facsimile of it in a Lisp dialect yesterday; see my comment history. 1> (load "template") nil 2> (let ((fiel

On the contrary, I implemented a substantial facsimile of it in a Lisp dialect yesterday; see my comment history. 1> (load "template") nil 2> (let ((field "name") (table "customers")) (te `SELECT @field FROM @table`)) #S(template merge #<interpreted fun: lambda (#:self-0073)> strings #("SELECT " " FROM ") vals #("name" "customers")) 3> *2.(merge) "SELECT name FROM customers" 4> [*2.vals 0] "name" 5> (set [*2.vals 0] "id") "id" 6> *2.(merge) "SELECT id FROM customers" 7> (upd *2.vals (map upcase-str)) #("ID" "CUSTOMERS") 8> *2.(merge) "SELECT ID FROM CUSTOMERS" Unlike template strings, it was done in the language. There already are quasi-strings in the form of `...` syntax. We can quote that syntax (e.g. implicitly as a macro argument) and then pull apart its pieces to construct an object. It should work even in a years-out-of-date installation of the language. No new tooling is required; no changes to syntax highlighting in the editor, nothing. It's a parlor trick that doesn't have any uses. The structured log messages use case is the most promising, because it has a consumer which actually wants the interpolated pieces that it would otherwise have to hackily parse out. I predict that Python will eventually get dedicated HTML syntax: perhaps something that uses indentation to indicate element nesting. Let's "vibe pseudocode" a sketch: html: div (class='main' id='1'): p: "paragraph text" or whatever.

pphysch 2y ago
> Unlike template strings, it was done in the language. This is a disingenuous way to compare a LISP with a language that values syntactic convention and strives to be readable and maintainable by more than one person. > I predict that Python will eventually get dedicated HTML syntax: How do you assign this result to a variable? How is this any better than content: HTML = t"<p>Hello {name}</p>"
- kazinator 2y ago
  It's a true statement; I made a usable construct that causes template strings to be turned into objects, rather than to perform the string substitution. I did it without changing any syntax, or have to ship a new version of the language. Python has to ship a new version for this; there is no way for existing installations to use the code. I don't have to change anything in my editor setup. So who is it that values syntactic convention? t"abc" is a syntax errror in vast numbers of existing Python installations; how can we call it convention? > How do you assign this result to a variable? That's to be worked out. The "html:" fantasy construct could have a way to do that. When you think of assigning to a variable, the first thing that comes to mind is "a = b" syntax. But, look, the define construct in Python also assigns to a variable: define fun(arg): ... The imagined html construct could have arguments like to assign an object to a variable, or just spin out textual HTML into a specified stream. I don't want to get into it, but there are obvious ways it could be done such that it hits all sorts of requirements. > How is it any better It renders all of the following problems unrepresentable: mismatched angle brackets, mismatched or unclosed tags, bad attribute syntax, injection.

pphysch 2y ago

> Unlike template strings, it was done in the language. This is a disingenuous way to compare a LISP with a language that values syntactic convention and strives to be readable and maintainable by more than one person. > I predict that Python will eventually get dedicated HTML syntax: How do you assign this result to a variable? How is this any better than content: HTML = t"<p>Hello {name}</p>"

kazinator 2y ago
It's a true statement; I made a usable construct that causes template strings to be turned into objects, rather than to perform the string substitution. I did it without changing any syntax, or have to ship a new version of the language. Python has to ship a new version for this; there is no way for existing installations to use the code. I don't have to change anything in my editor setup. So who is it that values syntactic convention? t"abc" is a syntax errror in vast numbers of existing Python installations; how can we call it convention? > How do you assign this result to a variable? That's to be worked out. The "html:" fantasy construct could have a way to do that. When you think of assigning to a variable, the first thing that comes to mind is "a = b" syntax. But, look, the define construct in Python also assigns to a variable: define fun(arg): ... The imagined html construct could have arguments like to assign an object to a variable, or just spin out textual HTML into a specified stream. I don't want to get into it, but there are obvious ways it could be done such that it hits all sorts of requirements. > How is it any better It renders all of the following problems unrepresentable: mismatched angle brackets, mismatched or unclosed tags, bad attribute syntax, injection.