# Meta.parse supports interpolation?
**URL:** https://discourse.julialang.org/t/meta-parse-supports-interpolation/44677
**Category:** New to Julia
**Tags:** question
**Created:** [August 10, 2020, 12:30pm UTC](https://discourse.julialang.org/t/meta-parse-supports-interpolation/44677 "2020-08-10T12:30:08Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@Hawk](https://discourse.julialang.org/u/Hawk)
#### Post date: [August 10, 2020, 12:30pm UTC](https://discourse.julialang.org/t/meta-parse-supports-interpolation/44677/1 "2020-08-10T12:30:08Z")
It is confusing for me when I use Meta.parse() function as:
```julia
Julia> x = 2
Julia> Meta.parse(":(:(v = $x))")
:($(Expr(:quote,:($(Expr(quote,:(v = 2)))))))
```
In general, an interpolation with single $ in :(:($x)) should not interpolate the value of x (which is 2 in the above example).
Since the manual doesn’t mention the case, is this rule special to Meta.parse() function?
---
### Author:  [@mcabbott](https://discourse.julialang.org/u/mcabbott)
#### Post date: [August 10, 2020, 12:51pm UTC](https://discourse.julialang.org/t/meta-parse-supports-interpolation/44677/2 "2020-08-10T12:51:32Z")
It’s just doing string interpolation before Meta.parse is called at all, and doesn’t care what the string contains:
```julia
julia> x = 2;
julia> ":(:( :) v = $x )])" # nonsense
":(:( :) v = 2 )])"
julia> Meta.parse(ans)
ERROR: Base.Meta.ParseError("missing comma or ) in argument list")
```
---
### Author:  [@Hawk](https://discourse.julialang.org/u/Hawk)
#### Post date: [August 10, 2020, 1:00pm UTC](https://discourse.julialang.org/t/meta-parse-supports-interpolation/44677/3 "2020-08-10T13:00:10Z")
Oh, you are right, I have totally forgotten the string interpolation!
---
### Author:  [@Hawk](https://discourse.julialang.org/u/Hawk)
#### Post date: [August 10, 2020, 2:02pm UTC](https://discourse.julialang.org/t/meta-parse-supports-interpolation/44677/4 "2020-08-10T14:02:59Z")
By the way, is there any method to use Meta.parse to parse such form as:
```julia
":(:(v = $x))"
```
to see how Julia transform into internal AST form?
---
### Author:  [@yuyichao](https://discourse.julialang.org/u/yuyichao)
#### Post date: [August 10, 2020, 2:50pm UTC](https://discourse.julialang.org/t/meta-parse-supports-interpolation/44677/5 "2020-08-10T14:50:11Z")
The issue is on string, so you just need to produce the correct string. You can escape `$` with `\$`.
---
### Author:  [@simeonschaub](https://discourse.julialang.org/u/simeonschaub)
#### Post date: [August 10, 2020, 4:35pm UTC](https://discourse.julialang.org/t/meta-parse-supports-interpolation/44677/6 "2020-08-10T16:35:03Z")
You might also be interested in the `Meta.@dump` macro, which prints the AST you give it, so you could do e.g. `Meta.@dump :(v = $x)` to inspect the AST. If you want to know how these are actually generated internally, I’m afraid, you will have to [learn Lisp](https://github.com/JuliaLang/julia/blob/master/src/julia-parser.scm).