# How to get doc string of function programmatically?
**URL:** https://discourse.julialang.org/t/how-to-get-doc-string-of-function-programmatically/126513
**Category:** General Usage
**Tags:** question
**Created:** [March 3, 2025, 8:01pm UTC](https://discourse.julialang.org/t/how-to-get-doc-string-of-function-programmatically/126513 "2025-03-03T20:01:06Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@miles-1](https://discourse.julialang.org/u/miles-1)
#### Post date: [March 3, 2025, 8:01pm UTC](https://discourse.julialang.org/t/how-to-get-doc-string-of-function-programmatically/126513/1 "2025-03-03T20:01:06Z")
I’m trying to make a function that will get the doc string of a given function. I am confused why there is an issue in the code below:
```julia
using Markdown: plain
function get_doc_string(
f::Function
)::String
return plain(@doc f)
end
"""
Maximum infection density: maximum([u_t[2] for u_t in u])
"""
function qoi_max_I(u, t)
return maximum([u_t[2] for u_t in u])
end
z = qoi_max_I
println("Literal doc call and literal function name : $(plain(@doc qoi_max_I))")
println("Literal doc call and variable-stored function: $(plain(@doc z))")
println("get_doc_string and literal function name : $(get_doc_string(qoi_max_I))")
println("get_doc_string and variable-stored function : $(get_doc_string(z))")
```
My output is this:
```julia
Literal doc call and literal function name : Maximum infection density: maximum([u*t[2] for u*t in u])
Literal doc call and variable-stored function: Maximum infection density: maximum([u*t[2] for u*t in u])
get_doc_string and literal function name : No documentation found.
Binding `f` does not exist.
get_doc_string and variable-stored function : No documentation found.
Binding `f` does not exist.
```
How can I avoid this issue, or must I use `@doc` directly each time I need to collect doc strings?
---
### Author:  [@stevengj](https://discourse.julialang.org/u/stevengj)
#### Post date: [March 3, 2025, 8:09pm UTC](https://discourse.julialang.org/t/how-to-get-doc-string-of-function-programmatically/126513/2 "2025-03-03T20:09:47Z")
You can look at `@macroexpand doc foo` to see what it does. Under the hood, it needs a module and a symbol, e.g.:
```julia
get_doc_string(mod::Module, f::Function) = Docs.doc(Docs.Binding(mod, Symbol(f)))
```
See also [Public API for `Docs.doc` · Issue #52747 · JuliaLang/julia · GitHub](https://github.com/JuliaLang/julia/issues/52747)
---
### Author:  [@miles-1](https://discourse.julialang.org/u/miles-1)
#### Post date: [March 4, 2025, 12:05am UTC](https://discourse.julialang.org/t/how-to-get-doc-string-of-function-programmatically/126513/3 "2025-03-04T00:05:30Z")
Thanks very much! You meant `@macroexpand @doc foo`, yes? Is it discouraged to do something like this since `Docs.Binding` is private? I see that you commented on the github issue, perhaps this will be changed in the future