Btukfyl

In Cyrillic typography tradition you need to duplicate the math operators (+, =, -, x) on line break. Following this answer I can get it working in math mode. How can I make = duplicate on line break in text mode:

MWE:

documentclass{article}

usepackage{amsmath}



mathchardefmathequals=mathcode`=

begingrouplccode`~=`=

  lowercase{endgroupdef~}{mathequalsdiscretionary{}{thetextfont0=}{}}

AtBeginDocument{mathcode`=="8000 }



mathchardefmathplus=mathcode`+

begingrouplccode`~+`+

  lowercase{endgroupdef~}{mathplusdiscretionary{}{thetextfont0+}{}}

AtBeginDocument{mathcode`+="8000 }



begin{document}

In math mode: $a = b = c = d = e = f = g = h = i = j = k = l = m = n = o =

p = q = r = s = t = u = v = w = x = y = z + a + b + c + d + e + f + g + h +

i + j + k + l + m + n + o + p + q + r + s + t + u + v + w + x + y + z$



In Text mode: a  =  b = c = d = e = f = g = h = i = j = k = l = m = n = o =

p = q = r = s = t = u = v = w = x = y = z + a + b + c + d + e + f + g + h + i 

+ j + k + l + m + n + o + p + q + r + s + t + u + v + w + x + y + z

end{document}

documentclass{article}

usepackage{amsmath}



mathchardefmathequals=mathcode`=

begingrouplccode`~=`=

  lowercase{endgroupdef~}{mathequalsdiscretionary{}{thetextfont0=}{}}

AtBeginDocument{mathcode`=="8000 }



mathchardefmathplus=mathcode`+

begingrouplccode`~+`+

  lowercase{endgroupdef~}{mathplusdiscretionary{}{thetextfont0+}{}}

AtBeginDocument{mathcode`+="8000 }



newcommandz[1]{ifhmodeunskipfinobreak discretionary{#1}{#1}{#1}nobreak}



begin{document}

In math mode: $a = b = c = d = e = f = g = h = i = j = k = l = m = n = o =

p = q = r = s = t = u = v = w = x = y = z + a + b + c + d + e + f + g + h +

i + j + k + l + m + n + o + p + q + r + s + t + u + v + w + x + y + z$



In Text mode: a  z=  b z= c z= d z= e z= f z= g z= h z= i z= j z= k z= l z= m z= n z= o z=

p z= q z= r z= s z= t z= u z= v z= w z= x z= y z= z + a + b + c + d + e + f + g + h + i 

+ j + k + l + m + n + o + p + q + r + s + t + u + v + w + x + y + z

end{document}

or

documentclass{article}

usepackage{amsmath}



newcommandz[1]{relax

ifmmode

#1discretionary{}{thetextfont0 #1}{}%

else

ifhmodeunskipfinobreak discretionary{#1}{#1}{#1}nobreak

fi}



begin{document}

In math mode: $a z= b z= c z= d z= e z= f z= g z= h z= i z= j z= k z= l z= m z= n z= o z=

p z= q z= r z= s z= t z= u z= v z= w z= x z= y z= z + a + b + c + d + e + f + g + h +

i + j + k + l + m + n + o + p + q + r + s + t + u + v + w + x + y + z$



In Text mode: a  z=  b z= c z= d z= e z= f z= g z= h z= i z= j z= k z= l z= m z= n z= o z=

p z= q z= r z= s z= t z= u z= v z= w z= x z= y z= z + a + b + c + d + e + f + g + h + i 

+ j + k + l + m + n + o + p + q + r + s + t + u + v + w + x + y + z

end{document}