Vim offers the :profile command, which is really handy. But it is limited to Vim script -- when it comes to plugins implemented in python it isn't that helpful.
Currently I'm trying to understand what is causing a large delay on Denite. As it doesn't happen in vanilla Vim, but only on some specific conditions which I'm not sure how to reproduce, I couldn't find which setting/plugin is interfering.
So I turned to profiling, and this is what I got from :profile:
FUNCTION denite#vim#_start()
Defined: ~/.vim/bundle/denite.nvim/autoload/denite/vim.vim line 33
Called 1 time
Total time: 5.343388
Self time: 4.571928
count total (s) self (s)
1 0.000006 python3 << EOF
def _temporary_scope():
nvim = denite.rplugin.Neovim(vim)
try:
buffer_name = nvim.eval('a:context')['buffer_name']
if nvim.eval('a:context')['buffer_name'] not in denite__uis:
denite__uis[buffer_name] = denite.ui.default.Default(nvim)
denite__uis[buffer_name].start(
denite.rplugin.reform_bytes(nvim.eval('a:sources')),
denite.rplugin.reform_bytes(nvim.eval('a:context')),
)
except Exception as e:
import traceback
for line in traceback.format_exc().splitlines():
denite.util.error(nvim, line)
denite.util.error(nvim, 'Please execute :messages command.')
_temporary_scope()
if _temporary_scope in dir():
del _temporary_scope
EOF
1 0.000017 return []
(...)
FUNCTIONS SORTED ON TOTAL TIME
count total (s) self (s) function
1 5.446612 0.010563 denite#helper#call_denite()
1 5.396337 0.000189 denite#start()
1 5.396148 0.000195 <SNR>237_start()
1 5.343388 4.571928 denite#vim#_start()
(...)
I tried to use the python profiler directly by wrapping the main line:
import cProfile
cProfile.run(_temporary_scope(), '/path/to/log/file')
, but no luck -- just a bunch of errors from cProfile. Perhaps it is because the way python is started from Vim, as it is hinted here that it only works on the main thread.
I guess there should be an easier way of doing this.
The python profiler does work by enclosing the whole code,
cProfile.run("""
(...)
""", '/path/to/log/file')
, but it is not that helpful. Maybe it is all that is possible.
Related
I have an app that parses multiple Cisco show tech files. These files contain the output of multiple router commands in a structured way, let me show you an snippet of a show tech output:
`show clock`
20:20:50.771 UTC Wed Sep 07 2022
Time source is NTP
`show callhome`
callhome disabled
Callhome Information:
<SNIPET>
`show module`
Mod Ports Module-Type Model Status
--- ----- ------------------------------------- --------------------- ---------
1 52 16x10G + 32x10/25G + 4x100G Module N9K-X96136YC-R ok
2 52 16x10G + 32x10/25G + 4x100G Module N9K-X96136YC-R ok
3 52 16x10G + 32x10/25G + 4x100G Module N9K-X96136YC-R ok
4 52 16x10G + 32x10/25G + 4x100G Module N9K-X96136YC-R ok
21 0 Fabric Module N9K-C9504-FM-R ok
22 0 Fabric Module N9K-C9504-FM-R ok
23 0 Fabric Module N9K-C9504-FM-R ok
<SNIPET>
My app currently uses both SED and Python scripts to parse these files. I use SED to parse the show tech file looking for a specific command output, once I find it, I stop SED. This way I don't need to read all the file (these can get to be very big files). This is a snipet of my SED script:
sed -E -n '/`show running-config`|`show running`|`show running config`/{
p
:loop
n
p
/`show/q
b loop
}' $1/$file
As you can see I am using a multi address range in SED. My question specifically is, how can I achieve something similar in python? I have tried multiple combinations of flags: DOTALL and MULTILINE but I can't get the result I'm expecting, for example, I can get a match for the command I'm looking for, but python regex wont stop until the end of the file after the first match.
I am looking for something like this
sed -n '/`show clock`/,/`show/p'
I would like the regex match to stop parsing the file and print the results, immediately after seeing `show again , hope that makes sense and thank you all for reading me and for your help
You can use nested loops.
import re
def process_file(filename):
with open(filename) as f:
for line in f:
if re.search(r'`show running-config`|`show running`|`show running config`', line):
print(line)
for line1 in f:
print(line1)
if re.search(r'`show', line1):
return
The inner for loop will start from the next line after the one processed by the outer loop.
You can also do it with a single loop using a flag variable.
import re
def process_file(filename):
in_show = False
with open(filename) as f:
for line in f:
if re.search(r'`show running-config`|`show running`|`show running config`', line):
in_show = True
if in_show
print(line)
if re.search(r'`show', line1):
return
I am trying to understand debugging in jupyter notebooks. As per my understanding applying breakpoint() is the way to go about it but I am landing into a few issues that I describe below. I have a file named test_debugger.py in ./ that I am using as a prop in my little understanding endeavor.
#./test_debugger.py
def fun1(a):
print(a)
breakpoint()
if a > 3:
print(a+1)
breakpoint()
print(a+2)
breakpoint()
return None
Setup:
from test_debugger import *
Issues:
breakpoint() enters into debugging the interactive shell:
print(5)
breakpoint()
fun1(4)
breakpoint()
Running the above code gives me
5
--Return--
None
> <ipython-input-2-4276bdd18b42>(2)<module>()
1 print(5)
----> 2 breakpoint()
3 fun1(4)
4 breakpoint()
ipdb>
I press n and I want to jump to the next line in the cell but it gets into debugging the interactive shell I guess. Upon pressing nI get:
ipdb> n
[... skipped 1 hidden frame]
[... skipped 1 hidden frame]
[... skipped 1 hidden frame]
[... skipped 1 hidden frame]
> /home/nitin/miniconda/envs/nyraml386/lib/python3.8/site-packages/IPython/core/interactiveshell.py(3330)run_ast_nodes()
3328 to_run.append((node, 'single'))
3329
-> 3330 for node,mode in to_run:
3331 if mode == 'exec':
3332 mod = Module([node], [])
ipdb>
Question: How do I get the desired functionality of n (jump to next line in code written by me while remaining in the same function score) and s (jump to the next line in code written by me while switching the function scope wherever necessary).
PYTHONBREAKPOINT not available in jupyter notebook
The behavior expected: I have read that in case I want to disable all breakpoint() then I can set the env variable PYTHONBREAKPOINT to manage the behavior of breakpoint(). Specifically, I can set PYTHONBREAKPOINT=0 to disable breakpoint()
The behavior seen: PYTHONBREAKPOINT is not a variable available at all in jupyter notebook. Even if I set it equal to 0 that does not alter the disable breakpoint(). It is as if nothing happened
Question: How to manage breakpoint() when operating in jupyter notebooks. What is the way to bring in PYTHONBREAKPOINT into the notebook
I'm trying to get intero running. After install, opening a Haskell file from an existing stack project results in:
Debugger entered--Lisp error: (wrong-type-argument stringp nil)
signal(wrong-type-argument (stringp nil))
flycheck-buffer()
flycheck-buffer-automatically()
flycheck-perform-deferred-syntax-check()
set-window-buffer(#<window 1 on Lib.hs> #<buffer Lib.hs>)
window--display-buffer(#<buffer Lib.hs> #<window 1 on Lib.hs> reuse ((inhibit-same-window)))
display-buffer-same-window(#<buffer Lib.hs> ((inhibit-same-window)))
display-buffer(#<buffer Lib.hs> (display-buffer-same-window (inhibit-same-window)))
pop-to-buffer(#<buffer Lib.hs> (display-buffer-same-window (inhibit-same-window)) nil)
pop-to-buffer-same-window(#<buffer Lib.hs>)
find-file("~/test/src/Lib.hs" t)
funcall-interactively(find-file "~/test/src/Lib.hs" t)
call-interactively(find-file nil nil)
command-execute(find-file)
When I run flycheck-buffer in the same buffer, nothing happens, even when there are errors in the source code.
Here are the contents of my .emacs file:
(setq debug-on-error t)
(require 'package)
(add-to-list 'package-archives '("melpa" . "http://melpa.org/packages/") t)
(package-initialize)
(package-refresh-contents)
(package-install 'intero)
(add-hook 'haskell-mode-hook 'intero-mode)
Since I'm on Mac Os I also tried adding (as suggested on the flycheck page):
(package-install 'exec-path-from-shell)
(exec-path-from-shell-initialize)
But it makes no difference.
Here are the installed package versions:
$ ls ~/.emacs.d/elpa/
archives/
company-20191114.1356/
dash-20191109.1327/
epl-20180205.2049/
flycheck-20191126.1329/
haskell-mode-20191120.1923/
intero-20191103.1239/
pkg-info-20150517.1143/
This is using GNU Emacs 26.3.
TL;DR
I found two issues and a (at least temporary) fix for each of them.
I am submitting pull requests for both of them, but in the mean time you can fix the issue for yourself either by editing the intero.el file directly, or (recommended way) by using the great el-patch package.
1) intero-ghc-version not set
This is due to the fact of using the intero-ghc-version local variable instead of calling the function (intero-ghc-version) in the intero-ghci-output-flags function (L.2668) intero.el
Fix: patch the function intero-ghci-output-flags :
replace
(split-string intero-ghc-version "\\."))))
by
(split-string (intero-ghc-version) "\\."))))
(notice the added parentheses)
2) misuse of append for string concatenation in intero-start-process-in-buffer
append is for lists, concat is for strings, an easy mistake, especially when in Haskell String is equivalent to [Char] (so technically... a list!)
fix: patch the function intero-start-process-in-buffer, L.2335 of the intero.el:
replace
(process-send-string process (append ":set " flag "\n")))
by
(process-send-string process (concat ":set " flag "\n")))
line 2335 of the current version of the source code, using el-patch)
Once these modifications are made, you should be up and running!
Initial answer
Same issue here.
Not a definitive answer, but I have the same issue and might have pinned down the issue to the function intero-ghci-output-flags being run as the intero-ghc-version variable is not set properly.
Feel free to correct me as I might have missed some things.
By following the error messages, I confirm it happens in (flycheck-start-current-syntax-check checker) in the flycheck-buffer function.
Running this directly from the haskell buffer shows that the error happens when calling (split-string intero-ghc-version "\\.") from the intero-ghci-output-flags function in the intero.el file (Line 2671).
This tries to split the intero version (as set by the intero-ghc-version function above in the file).
It seems the variable's value is nil, as confirmed by running M-x describe-variable -> intero-ghc-version.
During my tests I got seemingly imprevisible results from (intero-ghc-version).
Sometimes (at least on the first run?) it returns "8.4.4",
sometimes it fails with "Wrong type argument: stringp, (58 115 101 116 32 45 102 111 98 106 ...)
I am able to manually run the function intero-ghci-output-flags and get the proper output without error, once, and it fails if I run it a second time.
the function (intero-ghc-version-raw) consistently returns "8.4.4" however.
After experimenting the error message that spontaneously appears is transformed to:
Debugger entered--Lisp error: (wrong-type-argument stringp (58 115 101 116 32 45 102 111 98 106 101 99 116 45 99 111 100 101 . "\n"))
process-send-string(#<process stack> (58 115 101 116 32 45 102 111 98 106 101 99 116 45 99 111 100 101 . "\n"))
#f(compiled-function (flag) #<bytecode 0x1785fe9>)("-fobject-code")
mapc(#f(compiled-function (flag) #<bytecode 0x1785fe9>) ("-fobject-code"))
intero-start-process-in-buffer(#<buffer intero:backend:pubiber /home/mika/programmation/haskell/pubiber> nil #<buffer Lib.hs> nil)
intero-get-worker-create(backend nil #<buffer Lib.hs> nil)
intero-buffer(backend)
intero-eldoc()
The ASCII char sequence in the error message is ":set -fobject-code".
The "-fobject-code" in the message is the result of the intero-ghci-output-flags function, so it seems it finally worked properly but the rest of the code failed.
Note:
The fact that the file gets re-evaluated whenever intero tries to start a session might to explain why I get inconsistent results when running the functions several times.
PS running arch linux, system updated a few minutes ago, all emacs package updated.
---- EDIT ----
So after looking a bit more, in the function intero-start-process-in-buffer, that uses the flags to start the intero process in the lines 2334-2337:
(set-process-query-on-exit-flag process nil)
(mapc
(lambda (flag)
(process-send-string process (append ":set " flag "\n")))
(intero-ghci-output-flags))
(process-send-string process ":set -fdefer-type-errors\n")
they use append instead of concat to create the command.
replacing append by concat fixes this second error, and intero boots normally and seems to work properly (after setting intero-ghc-version).
---- EDIT 2 ----
Just figured out the original issue:
The function uses the variable intero-ghc-version instead of calling the function with the same name. The function is supposed to act as a lazy loader of the value, calling intero-ghc-version-raw the first time, and returning the cached value the subsequent times.
Calling the variable directly didn't allow the value to be set initially.
See the TL;DR for the temporary fix.
I'm trying to parallelize a script that prints out how many documents, pictures and videos there are in a directory as well as some other informations. I've put the serial script at the end of this message. Here's one example that shows how it outputs the informations about the directory given :
7 documents use 110.4 kb ( 1.55 % of total size)
2 pictures use 6.8 Mb ( 98.07 % of total size)
0 videos use 0.0 bytes ( 0.00 % of total size)
9 others use 26.8 kb ( 0.38 % of total size)
Now, I would like to use threads to minimize the execution time. I've tried this :
import threading
import tools
import time
import os
import os.path
directory_path="Users/usersos/Desktop/j"
cv=threading.Lock()
type_=["documents","pictures","videos"]
e={}
e["documents"]=[".pdf",".html",".rtf",".txt"]
e["pictures"]=[".png",".jpg",".jpeg"]
e["videos"]=[".mpg",".avi",".mp4",".mov"]
class type_thread(threading.Thread):
def __init__(self,n,e_):
super().__init__()
self.extensions=e_
self.name=n
def __run__(self):
files=tools.g(directory_path,self.extensions)
n=len(files)
s=tools.size1(files)
p=s*100/tools.size2(directory_path)
cv.acquire()
print("{} {} use {} ({:10.2f} % of total size)".format(n,self.name,tools.compact(s),p))
cv.release()
types=[type_thread(t,e[t]) for t in type_]
for t in types:
t.start()
for t in types:
t.join()
When I run that, nothing is printed out ! And when I key in 't'+'return key' in the interpreter, I get <type_thread(videos, stopped 4367323136)> What's more, sometimes the interpreter returns the right statistics with these same keys.
Why is that ?
Initial script (serial) :
import tools
import time
import os
import os.path
type_=["documents","pictures","videos"]
all_=type_+["others"]
e={}
e["documents"]=[".pdf",".html",".rtf",".txt"]
e["pictures"]=[".png",".jpg",".jpeg"]
e["videos"]=[".mpg",".avi",".mp4",".mov"]
def statistic(directory_path):
#----------------------------- Computing ---------------------------------
d={t:tools.g(directory_path,e[t]) for t in type_}
d["others"]=[os.path.join(root,f) for root, _, files_names in os.walk(directory_path) for f in files_names if os.path.splitext(f)[1].lower() not in e["documents"]+e["pictures"]+e["videos"]]
n={t:len(d[t]) for t in type_}
n["others"]=len(d["others"])
s={t:tools.size1(d[t]) for t in type_}
s["others"]=tools.size1(d["others"])
s_dir=tools.size2(directory_path)
p={t:s[t]*100/s_dir for t in type_}
p["others"]=s["others"]*100/s_dir
#----------------------------- Printing ---------------------------------
for t in all_:
print("{} {} use {} ({:10.2f} % of total size)".format(n[t],t,tools.compact(s[t]),p[t]))
return s_dir
Method start() seems not to work. When I replace
for t in types:
t.start()
for t in types:
t.join()
with
for t in types:
t.__run__()
It works fine (at least for now, I don't know if it will still when I'll add other commands).
I have the following code block in my .lhs file which uses inline TeX comments:
\begin{code}
main = print 0
{-"$\langle$Link$\rangle$"-}
\end{code}
However, after compiling with lhs2TeX, I get the following errors when compiling the generated .tex file:
! Missing $ inserted.
<inserted text>
$
l.269 \end{hscode}
\resethooks
I've inserted a begin-math/end-math symbol since I think
you left one out. Proceed, with fingers crossed.
! LaTeX Error: Bad math environment delimiter.
See the LaTeX manual or LaTeX Companion for explanation.
Type H <return> for immediate help.
...
l.269 \end{hscode}
\resethooks
Your command was ignored.
Type I <command> <return> to replace it with another command,
or <return> to continue without it.
! Missing $ inserted.
<inserted text>
$
l.269 \end{hscode}
\resethooks
I've inserted a begin-math/end-math symbol since I think
you left one out. Proceed, with fingers crossed.
! LaTeX Error: Bad math environment delimiter.
See the LaTeX manual or LaTeX Companion for explanation.
Type H <return> for immediate help.
...
l.269 \end{hscode}
\resethooks
Your command was ignored.
Type I <command> <return> to replace it with another command,
or <return> to continue without it.
! Missing $ inserted.
<inserted text>
$
l.269 \end{hscode}
\resethooks
I've inserted a begin-math/end-math symbol since I think
you left one out. Proceed, with fingers crossed.
! LaTeX Error: Bad math environment delimiter.
See the LaTeX manual or LaTeX Companion for explanation.
Type H <return> for immediate help.
...
l.269 \end{hscode}
\resethooks
Your command was ignored.
When I remove the " marks in the inline comment, the error disappears. Anyone know what's wrong?
P.S Here's the .tex file that lhs2TeX generates:
\documentclass{article}%% ODER: format == = "\mathrel{==}"
%% ODER: format /= = "\neq "
%
%
\makeatletter
\#ifundefined{lhs2tex.lhs2tex.sty.read}%
{\#namedef{lhs2tex.lhs2tex.sty.read}{}%
\newcommand\SkipToFmtEnd{}%
\newcommand\EndFmtInput{}%
\long\def\SkipToFmtEnd#1\EndFmtInput{}%
}\SkipToFmtEnd
\newcommand\ReadOnlyOnce[1]{\#ifundefined{#1}{\#namedef{#1}{}}\SkipToFmtEnd}
\usepackage{amstext}
\usepackage{amssymb}
\usepackage{stmaryrd}
\DeclareFontFamily{OT1}{cmtex}{}
\DeclareFontShape{OT1}{cmtex}{m}{n}
{<5><6><7><8>cmtex8
<9>cmtex9
<10><10.95><12><14.4><17.28><20.74><24.88>cmtex10}{}
\DeclareFontShape{OT1}{cmtex}{m}{it}
{<-> ssub * cmtt/m/it}{}
\newcommand{\texfamily}{\fontfamily{cmtex}\selectfont}
\DeclareFontShape{OT1}{cmtt}{bx}{n}
{<5><6><7><8>cmtt8
<9>cmbtt9
<10><10.95><12><14.4><17.28><20.74><24.88>cmbtt10}{}
\DeclareFontShape{OT1}{cmtex}{bx}{n}
{<-> ssub * cmtt/bx/n}{}
\newcommand{\tex}[1]{\text{\texfamily#1}} % NEU
\newcommand{\Sp}{\hskip.33334em\relax}
\newcommand{\Conid}[1]{\mathit{#1}}
\newcommand{\Varid}[1]{\mathit{#1}}
\newcommand{\anonymous}{\kern0.06em \vbox{\hrule\#width.5em}}
\newcommand{\plus}{\mathbin{+\!\!\!+}}
\newcommand{\bind}{\mathbin{>\!\!\!>\mkern-6.7mu=}}
\newcommand{\rbind}{\mathbin{=\mkern-6.7mu<\!\!\!<}}% suggested by Neil Mitchell
\newcommand{\sequ}{\mathbin{>\!\!\!>}}
\renewcommand{\leq}{\leqslant}
\renewcommand{\geq}{\geqslant}
\usepackage{polytable}
%mathindent has to be defined
\#ifundefined{mathindent}%
{\newdimen\mathindent\mathindent\leftmargini}%
{}%
\def\resethooks{%
\global\let\SaveRestoreHook\empty
\global\let\ColumnHook\empty}
\newcommand*{\savecolumns}[1][default]%
{\g#addto#macro\SaveRestoreHook{\savecolumns[#1]}}
\newcommand*{\restorecolumns}[1][default]%
{\g#addto#macro\SaveRestoreHook{\restorecolumns[#1]}}
\newcommand*{\aligncolumn}[2]%
{\g#addto#macro\ColumnHook{\column{#1}{#2}}}
\resethooks
\newcommand{\onelinecommentchars}{\quad-{}- }
\newcommand{\commentbeginchars}{\enskip\{-}
\newcommand{\commentendchars}{-\}\enskip}
\newcommand{\visiblecomments}{%
\let\onelinecomment=\onelinecommentchars
\let\commentbegin=\commentbeginchars
\let\commentend=\commentendchars}
\newcommand{\invisiblecomments}{%
\let\onelinecomment=\empty
\let\commentbegin=\empty
\let\commentend=\empty}
\visiblecomments
\newlength{\blanklineskip}
\setlength{\blanklineskip}{0.66084ex}
\newcommand{\hsindent}[1]{\quad}% default is fixed indentation
\let\hspre\empty
\let\hspost\empty
\newcommand{\NB}{\textbf{NB}}
\newcommand{\Todo}[1]{$\langle$\textbf{To do:}~#1$\rangle$}
\EndFmtInput
\makeatother
%
%
%
%
%
%
% This package provides two environments suitable to take the place
% of hscode, called "plainhscode" and "arrayhscode".
%
% The plain environment surrounds each code block by vertical space,
% and it uses \abovedisplayskip and \belowdisplayskip to get spacing
% similar to formulas. Note that if these dimensions are changed,
% the spacing around displayed math formulas changes as well.
% All code is indented using \leftskip.
%
% Changed 19.08.2004 to reflect changes in colorcode. Should work with
% CodeGroup.sty.
%
\ReadOnlyOnce{polycode.fmt}%
\makeatletter
\newcommand{\hsnewpar}[1]%
{{\parskip=0pt\parindent=0pt\par\vskip #1\noindent}}
% can be used, for instance, to redefine the code size, by setting the
% command to \small or something alike
\newcommand{\hscodestyle}{}
% The command \sethscode can be used to switch the code formatting
% behaviour by mapping the hscode environment in the subst directive
% to a new LaTeX environment.
\newcommand{\sethscode}[1]%
{\expandafter\let\expandafter\hscode\csname #1\endcsname
\expandafter\let\expandafter\endhscode\csname end#1\endcsname}
% "compatibility" mode restores the non-polycode.fmt layout.
\newenvironment{compathscode}%
{\par\noindent
\advance\leftskip\mathindent
\hscodestyle
\let\\=\#normalcr
\let\hspre\(\let\hspost\)%
\pboxed}%
{\endpboxed\)%
\par\noindent
\ignorespacesafterend}
\newcommand{\compaths}{\sethscode{compathscode}}
% "plain" mode is the proposed default.
% It should now work with \centering.
% This required some changes. The old version
% is still available for reference as oldplainhscode.
\newenvironment{plainhscode}%
{\hsnewpar\abovedisplayskip
\advance\leftskip\mathindent
\hscodestyle
\let\hspre\(\let\hspost\)%
\pboxed}%
{\endpboxed%
\hsnewpar\belowdisplayskip
\ignorespacesafterend}
\newenvironment{oldplainhscode}%
{\hsnewpar\abovedisplayskip
\advance\leftskip\mathindent
\hscodestyle
\let\\=\#normalcr
\(\pboxed}%
{\endpboxed\)%
\hsnewpar\belowdisplayskip
\ignorespacesafterend}
% Here, we make plainhscode the default environment.
\newcommand{\plainhs}{\sethscode{plainhscode}}
\newcommand{\oldplainhs}{\sethscode{oldplainhscode}}
\plainhs
% The arrayhscode is like plain, but makes use of polytable's
% parray environment which disallows page breaks in code blocks.
\newenvironment{arrayhscode}%
{\hsnewpar\abovedisplayskip
\advance\leftskip\mathindent
\hscodestyle
\let\\=\#normalcr
\(\parray}%
{\endparray\)%
\hsnewpar\belowdisplayskip
\ignorespacesafterend}
\newcommand{\arrayhs}{\sethscode{arrayhscode}}
% The mathhscode environment also makes use of polytable's parray
% environment. It is supposed to be used only inside math mode
% (I used it to typeset the type rules in my thesis).
\newenvironment{mathhscode}%
{\parray}{\endparray}
\newcommand{\mathhs}{\sethscode{mathhscode}}
% texths is similar to mathhs, but works in text mode.
\newenvironment{texthscode}%
{\(\parray}{\endparray\)}
\newcommand{\texths}{\sethscode{texthscode}}
% The framed environment places code in a framed box.
\def\codeframewidth{\arrayrulewidth}
\RequirePackage{calc}
\newenvironment{framedhscode}%
{\parskip=\abovedisplayskip\par\noindent
\hscodestyle
\arrayrulewidth=\codeframewidth
\tabular{#{}|p{\linewidth-2\arraycolsep-2\arrayrulewidth-2pt}|#{}}%
\hline\framedhslinecorrect\\{-1.5ex}%
\let\endoflinesave=\\
\let\\=\#normalcr
\(\pboxed}%
{\endpboxed\)%
\framedhslinecorrect\endoflinesave{.5ex}\hline
\endtabular
\parskip=\belowdisplayskip\par\noindent
\ignorespacesafterend}
\newcommand{\framedhslinecorrect}[2]%
{#1[#2]}
\newcommand{\framedhs}{\sethscode{framedhscode}}
% The inlinehscode environment is an experimental environment
% that can be used to typeset displayed code inline.
\newenvironment{inlinehscode}%
{\(\def\column##1##2{}%
\let\>\undefined\let\<\undefined\let\\\undefined
\newcommand\>[1][]{}\newcommand\<[1][]{}\newcommand\\[1][]{}%
\def\fromto##1##2##3{##3}%
\def\nextline{}}{\) }%
\newcommand{\inlinehs}{\sethscode{inlinehscode}}
% The joincode environment is a separate environment that
% can be used to surround and thereby connect multiple code
% blocks.
\newenvironment{joincode}%
{\let\orighscode=\hscode
\let\origendhscode=\endhscode
\def\endhscode{\def\hscode{\endgroup\def\#currenvir{hscode}\\}\begingroup}
%\let\SaveRestoreHook=\empty
%\let\ColumnHook=\empty
%\let\resethooks=\empty
\orighscode\def\hscode{\endgroup\def\#currenvir{hscode}}}%
{\origendhscode
\global\let\hscode=\orighscode
\global\let\endhscode=\origendhscode}%
\makeatother
\EndFmtInput
%
\begin{document}\section{}Precis 0
\newline{}\subsubsection*{\texttt{test0.tweave:}}\begin{hscode}\SaveRestoreHook
\column{B}{#{}>{\hspre}l<{\hspost}#{}}%
\column{E}{#{}>{\hspre}l<{\hspost}#{}}%
\>[B]{}\Varid{main}\mathrel{=}\Varid{print}\;\mathrm{0}{}\<[E]%
\\
\>[B]{}$\langle$Link$\rangle${}\<[E]%
\ColumnHook
\end{hscode}\resethooks
\section{}Precis 1
\newline{}\subsubsection*{\texttt{test0.tweave:}}\begin{hscode}\SaveRestoreHook
\column{B}{#{}>{\hspre}l<{\hspost}#{}}%
\column{E}{#{}>{\hspre}l<{\hspost}#{}}%
\>[B]{}\Varid{accum}\;\Varid{i}\mathrel{=}\Varid{id}{}\<[E]%
\ColumnHook
\end{hscode}\resethooks
\end{document}
The {-" ... "-} construct is quite low-level. It drops you in the environment TeX currently is in, which happens to be math mode already. So the solution to your problem is simple. Write the code to be inserted as if you are in math mode.
A different option is to use a normal comment, but make the comment characters invisible using \invisiblecomments. Normal comments are typeset as text by lhs2TeX.
The following complete lhs2TeX document demonstrates both options:
\documentclass{article}
%include polycode.fmt
\begin{document}
% Assume you are in math mode already:
\begin{code}
main = print 0
{-"\langle\text{Link}\rangle"-}
\end{code}
% This works, too:
\invisiblecomments
\begin{code}
main = print 0
{- $\langle$Link$\rangle$ -}
\end{code}
\end{document}